JP2006027290A - Collision mode determination apparatus and occupant crash protector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a collision mode determination apparatus capable of determining whether the collision mode of a vehicle is a head-on collision (a full-lap collision) or a non-head-on collision (an offset collision, an oblique collision, etc.) by using a single acceleration sensor. <P>SOLUTION: For the acceleration waveform caused by a collision of a vehicle, the number of occurrences of the amplitude exceeding the amplitude determination threshold in the deceleration direction +L1 (the number of occurrences of the amplitude in which the ridge of the waveform exceeds the first amplitude level in the deceleration direction +L1), and the number of occurrences of the amplitude exceeding the amplitude determination threshold in the acceleration direction -L1 (the number of occurrences of the amplitude in which the valley of the waveform exceeds the first amplitude level -L1 in the acceleration direction -L1) are counted, respectively. When both numbers of occurrences are substantially same, the collision is determined as a head-on collision (a full-lap collision). If the number of occurrences of the amplitude exceeding the amplitude determination threshold in the deceleration direction +L1 is considerably larger than the number of occurrences of the amplitude exceeding the amplitude determination threshold in the acceleration direction -L1, the collision is determined as a non-head-on collision (an offset collision, an oblique collision, etc.). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a collision type determination device that determines whether a vehicle collision type is a frontal collision or a non-frontal collision (offset collision, diagonal collision, etc.), and an occupant protection device that includes the collision type determination device.

  Phase differences between detection outputs of first and second acceleration sensors, and first and second acceleration sensors, which are arranged on the left and right at the front of the vehicle and detect acceleration based on a collision with an obstacle of the vehicle Is determined to be one of frontal collision, underride collision, and pole collision of the vehicle, and when the phase difference between the detection outputs of the first and second acceleration sensors is large, the collision is A vehicle occupant protection system determination device that includes a determination unit that determines that the vehicle is one of oblique collisions has been proposed (see Patent Document 1).

  When the time integral value of the floor G from the floor sensor attached near the center console of the vehicle is less than the threshold value and larger than the threshold value of the front G from the front sensor attached to the front center of the vehicle, There has been proposed a collision type discrimination device that determines that the applied impact is a normal collision soft crash (see Patent Document 2).

  An acceleration sensor that detects an impact at the time of a vehicle collision, a first comparison unit that compares an output signal of the acceleration sensor and a first threshold value, and a first within a predetermined interval that is shifted in units of unit time An integration means for integrating the output of the comparison means, a second comparison means for comparing the integrated value of the integration means with a second threshold value to determine whether or not the occupant protection means needs to be activated, and a second comparison Providing a starting means for controlling the starting of the occupant protection means based on the output signal from the means, thereby distinguishing soft crashes (such as offset collisions and underride collisions) in which a relatively low acceleration signal continues for a long time from low-speed frontal collisions. Separately, a vehicle collision determination device has been proposed in which the occupant protection means can be activated at an appropriate timing (see Patent Document 3).

  A deceleration detecting means for detecting a vehicle deceleration in the longitudinal direction of the vehicle disposed in the center of the vehicle main body, and from when a vehicle deceleration waveform detected by the deceleration detecting means exceeds a preset threshold value A peak time detecting means for detecting the time until the first peak as the first peak time, and a time when the deceleration integrated value obtained by integrating the vehicle deceleration with the time becomes equal to the preset required integrated value is detected as the required time. There has been proposed a collision type discriminating apparatus including a requested value time detecting means for performing and a form judging means for judging a vehicle collision form based on a first peak time and a requested time (see Patent Document 4).

  Based on detection values of the first impact detection means provided at the left front portion of the vehicle, the second impact detection means provided at the right front portion of the vehicle, and the first and second impact detection means. The collision mode is classified into one of normal collision, offset collision and oblique collision, and accuracy calculation means for determining the accuracy of the classified collision type, and control of activation of the occupant protection device based on the accuracy calculated by the accuracy calculation means An activation control device for an occupant protection device has been proposed (see Patent Document 5).

A first collision determination signal is output by detecting an acceleration signal at the initial stage of the collision arranged at the front end of the vehicle, and a second collision determination signal is detected by detecting an acceleration signal at a level higher than the subsequent initial stage. A first collision detection unit that outputs a first collision detection signal that is disposed on the vehicle interior side and detects a collision signal at the initial stage of the collision, and outputs a third collision determination signal. A second collision detection unit that detects a signal and outputs a fourth collision determination signal; a first AND gate that calculates a logical product of the first and third collision determination signals and outputs a first airbag deployment signal; A second AND gate that takes a logical product of the second and fourth collision determination signals and outputs a second airbag deployment signal, and receives the first airbag deployment signal to semi-deploy the airbag Let Occupant protection system for all deploy the airbag receives the second round airbag inflation signal is known (see Patent Document 6).
JP 11-194137 A JP 2001-247003 A Japanese Patent Laid-Open No. 2003-43060 JP 2003-90844 A JP 2003-261003 A JP 2001-10441 A

  Various methods, such as a method using a single acceleration sensor and a method using a plurality of acceleration sensors, have been proposed to discriminate a vehicle collision mode, and what type of collision is accurately detected, etc. Various schemes have also been proposed. Further, various methods have been proposed depending on how and at what timing the airbag device is deployed based on the result of determining the vehicle collision mode.

  In a two-stage airbag apparatus, when a collision that requires the airbag apparatus to be activated is detected, the airbag is first semi-deployed, and if the collision is at a high speed, the airbag is fully deployed. When the collision type is an offset collision or an oblique collision, the timing of fully deploying the airbag may be delayed or not fully deployed. This is because the acceleration waveform detected by the acceleration sensor at the time of offset collision or oblique collision is close to the waveform at the time of low-speed frontal collision (low-speed full-wrap collision).

  FIG. 6 is a graph showing the above problem. The horizontal axis represents the elapsed time from the time of occurrence of the collision, and the vertical axis represents the integrated value of the acceleration detected by the acceleration sensor (time integrated value from the time of occurrence of the collision). The acceleration sensor may be one attached to the substantially central portion of the vehicle (center G sensor) or one attached to the front end portion of the vehicle (front G sensor). th1 is a threshold value for igniting the first stage inflator, and th2 is a threshold value for igniting the second stage inflator. Symbol a indicates the change characteristic of the integral value in the case of a low-speed (for example, 26 km / h) frontal collision. Symbol b indicates the change characteristic of the integral value in the case of a high-speed (for example, 35 km / h) frontal collision. Symbol c indicates the change characteristic of the integral value in the case of high-speed offset collision and high-speed oblique collision (for example, offset collision at 64 km / h and oblique collision at 40 km / h). As indicated by reference symbol c, in the case of a high-speed oblique collision and a high-speed offset collision, the integrated value of acceleration exceeds the first threshold th1 but does not exceed the second threshold th2. Yes, the second stage inflator may not be ignited. In the case of high-speed oblique collision and high-speed offset collision, it may take time for the integrated value of acceleration to reach the second threshold value, and the ignition timing of the second stage inflator may not be appropriate. .

  The present invention has been made to solve such a problem, and uses a single acceleration sensor to determine whether the vehicle collision type is a frontal collision or a non-frontal collision (offset collision, diagonal collision, etc.). An object is to provide a collision type discrimination device. It is another object of the present invention to provide an occupant protection device that is equipped with a collision type discrimination device so that a two-stage airbag device can be deployed at an appropriate timing corresponding to each collision type.

  In order to solve the above-described problems, a collision type determination device according to the present invention includes an acceleration sensor that detects acceleration in the longitudinal direction of a vehicle, and whether or not the amplitude of a detection output signal of the acceleration sensor is in both the deceleration direction and the acceleration direction. And a collision type determination unit that determines whether the vehicle collision type is a frontal collision or a non-frontal collision (offset collision, diagonal collision, etc.) based on whether the vehicle is in the deceleration direction.

  An occupant protection device according to the present invention generates an acceleration sensor that detects acceleration in the longitudinal direction of a vehicle, and a count start command when acceleration detected by the acceleration sensor exceeds a preset collision detection threshold. A count start control means, an acceleration direction first amplitude level occurrence count counting means for counting the number of acceleration direction amplitude occurrences exceeding a preset acceleration direction amplitude determination threshold value from the time when the count start command is generated, and counting Deceleration direction first amplitude level occurrence count counting means for counting the number of occurrences of deceleration direction amplitude exceeding a preset deceleration direction amplitude determination threshold from the time when the start command is generated, and when the count start command is generated A second decelerating direction second amplitude level counting means for counting the number of occurrences of an amplitude exceeding a preset threshold value for determining the first stage deployment of the airbag from Acceleration direction for counting the number of occurrences of an amplitude that is larger than the airbag first stage deployment determination reference threshold value from the time when the command is generated and exceeds a preset airbag second stage deployment determination reference threshold value Based on the count value of the third amplitude level occurrence count counting means, the count value of the acceleration direction first amplitude level occurrence count counting means, and the count value of the deceleration direction first amplitude level occurrence count counting means, the vehicle collision mode is a frontal collision. Or the collision type determination means for determining whether the collision is a non-frontal collision (offset collision, diagonal collision, etc.) and the count value of the deceleration direction second amplitude level occurrence number counting means are set to the preset first airbag deployment threshold value. If the count value of the airbag first-stage deployment command generating means for generating the airbag first-stage deployment command and the deceleration direction third amplitude level generation frequency counting means is preset, Count values of the second-stage deployment command generation means for frontal collision airbag that generates an airbag second-stage deployment command when the second-stage deployment threshold of the bag is reached, and a deceleration direction third amplitude level generation count counting means A non-frontal collision airbag second-stage deployment command generating means for generating an airbag second-stage deployment command when the air pressure reaches a preset non-frontal collision airbag second-stage deployment threshold; Airbag deployment drive means for igniting the first stage inflator of the airbag device based on the first stage deployment command and igniting the second stage inflator of the airbag device based on the airbag second stage deployment command; It is characterized by providing.

  The collision type determination device according to the present invention determines whether the vehicle collision type is a frontal collision (full lap collision) or a non-frontal collision (offset collision or oblique collision) based on the detection output of a single acceleration sensor. it can.

  The occupant protection device according to the present invention can determine whether the collision type of the vehicle is a frontal collision or a non-frontal collision (offset collision or oblique collision) based on the detection output of a single acceleration sensor. Even if the collision mode is an offset collision or an oblique collision, the second stage inflator can be operated accurately when the collision is a large impact such as a high-speed collision.

  Hereinafter, the best mode for carrying out the invention will be described based on examples.

  FIG. 1 is a block diagram of a collision type discrimination device according to an embodiment of the present invention. A collision type determination device 1 according to an embodiment of the present invention includes an acceleration sensor 2 and a collision type determination unit 3. The collision mode determination unit 3 includes an LPF (low-pass filter) 11, an A / D conversion unit 12, a count start control unit 13, an acceleration direction first amplitude level generation number counting unit 14, and a deceleration direction first amplitude level generation number counting unit 15. And a collision mode determination means 16.

  The acceleration sensor 2 is attached to the approximate center of the vehicle (for example, the floor tunnel portion in the passenger compartment or the floor near the shift lever). The acceleration sensor 2 detects the acceleration in the longitudinal direction of the vehicle and outputs an acceleration detection signal. The acceleration sensor 2 outputs the acceleration in the deceleration direction (deceleration acceleration) as a positive (+) value when the output voltage when no acceleration is applied is 0, and the acceleration in the acceleration direction is negative (−). Output as a value. In addition, the acceleration sensor 2 may be attached to the approximate center (for example, the vicinity of a radiator grill) of the vehicle front part.

  From the acceleration detection output signal of the acceleration sensor 2, a high frequency noise component is removed by the LPF 11 and a low frequency component related to a vehicle collision is extracted and supplied to the A / D converter 12. It is converted into an acceleration signal (acceleration data). Note that a high-pass filter (not shown) may be provided in front of the LPF 11 to eliminate the influence of drift in the output voltage of the acceleration sensor 2. The digital acceleration signal (acceleration data) output from the A / D converter 12 is supplied to the count start control means 13, the acceleration direction first amplitude level generation count counting means 14, and the deceleration direction first amplitude level generation count counting means 15. Is done.

  The count start control means 13 constantly monitors acceleration based on the digital acceleration signal (acceleration data), and when the acceleration (deceleration acceleration) exceeds a preset collision detection threshold (for example, 2G to 4G). A counting start command 13a is generated. The count start control means 13 generates a reset command 13b when the acceleration is less than a preset collision detection threshold (for example, 2G to 4G) for a preset time (for example, 100 milliseconds). To do. The count start command 13a and the reset command 13b are supplied to the acceleration direction first amplitude level generation count counting means 14, the deceleration direction first amplitude level generation count counting means 15, and the collision mode determination means 16, respectively.

  FIG. 2 is a diagram for explaining the operation of the acceleration direction first amplitude level occurrence count counting means and the deceleration direction first amplitude level occurrence count counting means. The horizontal axis indicates time, and the vertical axis indicates the acceleration detected by the acceleration sensor 2. K is an acceleration waveform showing an example of acceleration change. + Gs is a collision detection threshold, + L1 is a deceleration direction amplitude determination threshold (deceleration direction first amplitude level), and -L1 is an acceleration direction amplitude determination threshold (acceleration direction first amplitude level). t0 is the time when the acceleration first exceeds the collision detection threshold + Gs. 2 shows an example in which the absolute value of each amplitude determination threshold (first amplitude level) + L1, −L1 is set smaller than the collision detection threshold + Gs, each amplitude determination threshold ( The absolute value of (first amplitude level) + L1, -L1 may be the same value as the collision detection threshold value + Gs or may be a value larger than the collision detection threshold value + Gs.

  Each of the first amplitude level occurrence count counting means 14 and 15 starts its operation from the time t0 (the time when the count start command 13a is supplied) when the acceleration exceeds the collision detection threshold + Gs. The acceleration direction first amplitude level occurrence count counting means 14 counts the number of occurrences of the amplitude exceeding the acceleration direction first amplitude level −L1 (the number of occurrences of the amplitude waveform where the trough of the waveform exceeds the acceleration direction first amplitude level −L1). To do. The deceleration direction first amplitude level occurrence count counter 15 counts the number of occurrences of amplitude exceeding the deceleration direction first amplitude level + L1 (the number of occurrences of amplitude waveform where the peak of the waveform exceeds the deceleration direction first amplitude level + L1).

  As shown in FIG. 1, the count values (occurrence count data) of the first amplitude level occurrence count counting means 14 and 15 are respectively supplied to the collision form determination means 16. Each of the first amplitude level occurrence number counting means 14 and 15 stops counting when the reset command 13b is supplied, and sets the count value up to that point to zero.

  The collision type determination means 16 counts each count of the first amplitude level occurrence count counting means 14 and 15 when a preset time (for example, 20 to 40 milliseconds) elapses from the time when the count start command 13a is supplied. The collision mode is determined based on the output (occurrence frequency data), and the determination result is output. When the reset command 13b is supplied, the collision form determination means 16 clears the collision form determination result and stops outputting the collision form determination result. The collision mode is determined by the number of occurrences of amplitude exceeding the first deceleration level + L1 (number of peaks exceeding + L1) and the number of occurrences of amplitude exceeding the first amplitude level −L1 in the acceleration direction (number of valleys exceeding −L1). This is done by comparing

  FIG. 3 is an explanatory diagram of collision mode determination. FIG. 3A illustrates an acceleration waveform during a frontal collision, and FIG. 3B illustrates an example of an acceleration waveform during an offset collision or an oblique collision. As shown in FIG. 3A, in a frontal collision, a waveform having a mountain on the deceleration (+ G) side and a waveform having a valley on the acceleration (−G) side are almost alternately repeated. For this reason, the number of occurrences of amplitude exceeding the first amplitude level in the deceleration direction + L1 (number of peaks exceeding + L1) and the number of occurrences of amplitude exceeding the first amplitude level in the acceleration direction -L1 (number of valleys exceeding -L1) are almost equal. The same. As shown in FIG. 3B, in the offset collision and the oblique collision, a waveform having a deep valley on the acceleration (-G) side hardly appears. Therefore, the number of occurrences of amplitude exceeding the first amplitude level in the deceleration direction + L1 (the number of peaks exceeding + L1) is greater than the number of occurrences of the amplitude exceeding the first amplitude level in the acceleration direction -L1 (number of valleys exceeding -L1). Significantly more.

  The collision mode determination means 16 shown in FIG. 1 includes the number of occurrences of amplitude exceeding the first deceleration level + L1 (number of peaks exceeding + L1) and the number of occurrences of amplitude exceeding the first acceleration level −L1 (−L1). If the difference from the number of troughs exceeding 1) is small, a collision type determination result indicating a frontal collision is generated, and the number of occurrences of amplitude exceeding the first deceleration level + L1 in the deceleration direction (+ the number of peaks exceeding L1) is When the number of occurrences of the amplitude exceeding the first acceleration level −L1 in the acceleration direction (the number of valleys exceeding −L1) is significantly larger, a collision type determination result indicating that the collision is an offset collision or an oblique collision is generated. The collision mode determination means 16 determines the number of occurrences of amplitude exceeding the first deceleration level + L1 (number of peaks exceeding + L1) and the number of occurrences of amplitude exceeding the first amplitude level −L1 in the acceleration direction (valley exceeding −L1). The collision mode may be determined based on the ratio.

  The collision mode determination means 16 does not determine the collision mode at the time when a preset time (for example, 20 to 40 milliseconds) has elapsed from the time when the counting start command 13a is supplied, but each first amplitude. The collision mode may be determined when one of the count outputs (occurrence number data) of the level generation number counting means 14 and 15 reaches a preset value. Further, the collision mode determination means 16 may determine the collision mode when a first-stage deployment command is supplied to a two-stage airbag device (not shown).

  A two-stage airbag apparatus (not shown) ignites the second-stage inflator shown in FIG. 6 when it is determined by the collision type determination apparatus 1 that the non-frontal collision (offset collision, oblique collision, etc.) is performed. By changing the threshold th2 to a lower threshold or by multiplying the integral value of acceleration by a predetermined coefficient to increase the integral value, the second stage inflator can be reliably ignited. Can do.

  FIG. 4 is a block diagram of an occupant protection device according to an embodiment of the present invention. The occupant protection device 20 shown in FIG. 4 includes an acceleration sensor 2, an airbag deployment determination unit 4, an airbag deployment drive unit 5, and an airbag device 6.

  The acceleration sensor 2 is attached to the approximate center of the vehicle (for example, the floor tunnel portion in the passenger compartment or the floor near the shift lever). The acceleration sensor 2 detects the acceleration in the longitudinal direction of the vehicle and outputs an acceleration detection signal. The acceleration sensor 2 outputs the acceleration in the deceleration direction (deceleration acceleration) as a positive (+) value when the output voltage when no acceleration is applied is 0, and the acceleration in the acceleration direction is negative (−). Output as a value. In addition, the acceleration sensor 2 may be attached to the approximate center (for example, the vicinity of a radiator grill) of the vehicle front part.

  The airbag deployment determination means 4 includes a collision type determination unit 30, a deceleration direction second amplitude level generation count counting means 21, a deceleration direction third amplitude level generation count counting means 22, an airbag first stage deployment command generation means 23, a front surface. A collision airbag second-stage deployment command generation means 24 and a non-frontal collision airbag second-stage deployment command generation means 25 are provided.

  The collision mode determination unit 30 includes an LPF (low-pass filter) 11, an A / D conversion unit 12, a count start control unit 13, an acceleration direction first amplitude level generation number counting unit 14, and a deceleration direction first amplitude level generation number counting unit 15. And a collision mode determination means 31.

  From the acceleration detection output signal of the acceleration sensor 2, a high frequency noise component is removed by the LPF 11 and a low frequency component related to a vehicle collision is extracted and supplied to the A / D converter 12. It is converted into an acceleration signal (acceleration data). Note that a high-pass filter (not shown) may be provided in front of the LPF 11 to eliminate the influence of drift in the output voltage of the acceleration sensor 2. The digital acceleration signal (acceleration data) output from the A / D converter 12 includes a count start control unit 13, an acceleration direction first amplitude level generation number counting unit 14, a deceleration direction first amplitude level generation number counting unit 15, and a deceleration. This is supplied to the direction second amplitude level occurrence count counting means 21 and the deceleration direction third amplitude level occurrence count counting means 22, respectively.

  The count start control means 13 constantly monitors acceleration based on the digital acceleration signal (acceleration data), and when the acceleration (deceleration acceleration) exceeds a preset collision detection threshold (for example, 2G to 4G). A counting start command 13a is generated. The count start control means 13 generates a reset command 13b when the acceleration is less than a preset collision detection threshold (for example, 2G to 4G) for a preset time (for example, 100 milliseconds). To do. The count start command 13a and the reset command 13b are respectively supplied to the amplitude level generation number counting means 14, 15, 21, 22 and the collision mode determining means 31. The count start command 13a is supplied to each deployment command generation means 23, 24, 25.

  FIG. 5 is a diagram for explaining the operation of each amplitude level occurrence number counting means. The horizontal axis indicates time, and the vertical axis indicates the acceleration detected by the acceleration sensor 2. K is an acceleration waveform showing an example of acceleration change. + Gs is a collision detection threshold value, -L1 is an acceleration direction first amplitude level (acceleration direction amplitude determination threshold value), + L1 is a deceleration direction first amplitude level (deceleration direction amplitude determination threshold value), and + L2 is an airbag 1 A stage deployment determination reference threshold, + L3 is an airbag second stage deployment determination reference threshold. The airbag first stage deployment determination reference threshold value + L2 is set to a value larger than the collision detection threshold value + Gs. The airbag second stage deployment determination reference threshold L3 is set to a value larger than the airbag first stage deployment determination reference threshold + L2.

  Each amplitude level occurrence number counting means 14, 15, 21, 22 starts counting operation from the time when the count start command 13a is supplied (time t0 when the acceleration exceeds the collision detection threshold). The acceleration direction first amplitude level occurrence count counting means 14 counts the number of occurrences of an amplitude exceeding the acceleration direction first amplitude level (acceleration direction amplitude determination threshold) −L1. The deceleration direction first amplitude level occurrence count counter 15 counts the number of occurrences of amplitude exceeding the deceleration direction first amplitude level (deceleration direction amplitude determination threshold) + L1. The deceleration direction second amplitude level occurrence count counting means 21 counts the number of occurrences of the amplitude exceeding the airbag first stage deployment determination reference threshold + L2. The deceleration direction third amplitude level occurrence count counter 22 counts the number of occurrences of the amplitude exceeding the airbag second stage deployment determination reference threshold + L3. Each amplitude level occurrence number counting means 14, 15, 21, 22 stops counting when the reset command 13b is supplied, and sets the count value so far to zero.

  The count value of the acceleration direction first amplitude level occurrence number counting means 14 is supplied to the collision type determination means 31. The count value of the decelerating direction first amplitude level occurrence number counting means 15 is supplied to the collision type determining means 31. The collision mode determination means 31 includes a time point when a preset time (for example, 20 to 40 milliseconds) has elapsed from the time point when the count start command 13a is supplied, or the time point when the airbag first stage deployment command is generated. Based on the count value of the acceleration direction first amplitude level occurrence count counting means 14 and the count value of the deceleration direction first amplitude level occurrence count counting means 15 at the earlier time point, the collision mode is a frontal collision or a non-frontal collision. It is determined whether it is (offset collision, diagonal collision, etc.), and the collision type determination result is output. For example, when the count value of the deceleration direction first amplitude level occurrence count counting means 15 is more than twice the count value of the acceleration direction first amplitude level occurrence count counting means 14, non-frontal collision (offset collision or oblique collision) ), And if not, a frontal collision is determined. When the reset command 13b is supplied, the collision form determination unit 31 clears the collision form determination result and stops outputting the collision form determination result. The collision mode determination result is supplied to the front-collision airbag second-stage deployment command generating means 24 and the non-frontal collision airbag second-stage deployment command generating means 25.

  The count value of the deceleration direction second amplitude level generation number counting means 21 is supplied to the airbag first stage deployment command generating means 23. The airbag first-stage deployment command generation means 23 reduces the second amplitude level in the deceleration direction between the time when the count start command 13a is supplied and the preset first-stage airbag deployment allowable time (for example, 50 milliseconds). An airbag first stage deployment command is generated when the count value of the generation number counting means 21 reaches a preset first stage deployment threshold value of the airbag. The airbag first stage deployment command is supplied to the collision form determination means 31 and the first stage ignition circuit 51 in the airbag deployment drive means 5.

  The count value of the deceleration direction third amplitude level generation number counting means 22 is supplied to the front collision airbag second stage deployment command generation means 24 and the non-frontal collision airbag second stage deployment command generation means 25. The front collision airbag second-stage deployment command generating means 24 operates when the collision type determination result is a frontal collision. The front collision airbag second-stage deployment command generating means 24 is configured to reduce the speed in the deceleration direction between the time when the counting start command 13a is supplied and the preset second-stage airbag deployment allowable time (for example, 150 milliseconds). An airbag second-stage deployment command is generated when the count value of the 3-amplitude level occurrence number counting means 22 reaches a preset second-stage deployment threshold value for a frontal collision airbag. The airbag second stage deployment command is supplied to the second stage ignition circuit 52 in the airbag deployment drive means 5.

  The non-frontal collision airbag second-stage deployment command generation means 25 operates when the collision type determination result is a non-frontal collision (offset collision, diagonal collision, etc.). The non-frontal collision airbag second-stage deployment command generating means 25 decelerates between the time when the counting start command 13a is supplied and the preset second-stage airbag deployment allowable time (for example, 150 milliseconds). An airbag second-stage deployment command is generated when the count value of the third amplitude level generation number counting means 22 reaches a preset second-stage deployment threshold value for the non-frontal collision airbag. The airbag second stage deployment command is supplied to the second stage ignition circuit 52 in the airbag deployment drive means 5. The second-stage deployment threshold value for the non-frontal collision airbag is smaller than the second-stage deployment threshold value for the frontal collision airbag.

  The airbag second stage deployment command generating means 24 and the non-frontal collision airbag second stage deployment command generating means 25 are not provided, and one airbag second stage deployment command generating means 25 collides. It is good also as a structure which changes an airbag 2nd step | paragraph expansion | deployment threshold value based on a form determination result.

  The airbag device 6 is of a two-stage type including a first-stage inflator 61 and a second-stage inflator 62, and each gas generating material (illustrated) ignited by the first-stage and second-stage squibs 611, 621. (Not shown) and a bag (not shown) that is inflated by the generated gas.

  The airbag deployment drive means 5 energizes the first-stage squib 611 based on the first-stage ignition command and energizes the first-stage squib 611, and energizes the second-stage squib 621 based on the second-stage ignition command. And a second stage ignition circuit 52 for igniting.

  Next, the operation of the occupant protection device according to the embodiment of the present invention will be described. As shown in FIG. 5, the count start command 13a is generated from the count start control means 13 at a time t0 when the acceleration (deceleration) detected by the acceleration sensor 2 exceeds the collision detection threshold + Gs. The acceleration direction first amplitude level occurrence count counting means 14 counts the number of occurrences of an amplitude exceeding the acceleration direction first amplitude level (acceleration direction amplitude determination threshold) -L1, and the deceleration direction first amplitude level occurrence count counting means 14. Is used to count the number of occurrences of amplitude exceeding the first deceleration level amplitude level (deceleration direction amplitude determination threshold value) + L1.

  The number of occurrences of amplitude exceeding the airbag first stage deployment determination reference threshold + L2 is counted by the deceleration direction second amplitude level occurrence count counting means 21, and the counted value has reached the airbag first stage deployment threshold. Sometimes, the airbag first stage deployment command generating means 23 generates an airbag first stage deployment command, the first stage squib 611 is ignited via the first stage ignition circuit 51, and the first stage inflator 61 is activated. The airbag is half deployed (low pressure inflation). The collision form determination means 31 determines the collision form by the time when the airbag first stage deployment command is generated at the latest.

  If it is determined that the frontal collision has occurred, the airbag second-stage deployment command generation means 24 for frontal collision is the airbag second-stage deployment determination reference threshold value + L3 counted by the deceleration direction third amplitude level generation count counting means 22. An airbag second-stage deployment command is generated when the number of occurrences of the amplitude exceeding exceeds the airbag second-stage deployment threshold during frontal collision. As a result, the second-stage squib 621 is ignited via the second-stage ignition circuit 52, the second-stage inflator 62 is activated, and the airbag is fully deployed (high-pressure inflation). When the count value of the decelerating direction third amplitude level occurrence number counting means 22 has reached the second-stage deployment threshold value at the time of the frontal collision at the time when the frontal collision is determined, the airbag 2 immediately A stage expansion command is generated. That is, when the impact is extremely large due to high-speed collision or the like, the first and second stages of the airbag are deployed almost simultaneously.

  When it is determined as a non-frontal collision (offset collision, diagonal collision, etc.), the non-frontal collision airbag second-stage deployment command generation means 25 counts the airbag counted by the deceleration direction third amplitude level generation number counting means 22. An airbag second-stage deployment command is generated when the number of occurrences of amplitude exceeding the second-stage deployment determination reference threshold + L3 reaches the airbag second-stage deployment threshold for non-frontal collision. As a result, the second-stage squib 621 is ignited via the second-stage ignition circuit 52, the second-stage inflator 62 is activated, and the airbag is fully deployed (high-pressure inflation). Note that when the count value of the deceleration direction third amplitude level occurrence number counting means 22 has reached the second-stage deployment threshold value for the non-frontal collision airbag when it is determined that the non-frontal collision has occurred, the air A bag second-stage deployment command is generated. That is, when the impact is extremely large due to high-speed collision or the like, the first and second stages of the airbag are deployed almost simultaneously.

  In this way, it is determined whether the collision type is a frontal collision or a non-frontal collision (offset collision, oblique collision, etc.), and the airbag second-stage deployment threshold (deployment judgment condition) is changed according to the collision type. By doing so, the second-stage inflator 62 can be actuated accurately when the collision type is any of a frontal collision, an offset collision, and an oblique collision and is a high-speed collision.

  According to the present invention, it is possible to determine whether the vehicle collision mode is a frontal collision or a non-frontal collision (offset collision, oblique collision) based on the detection output of a single acceleration sensor. This is useful for an occupant protection device using an air bag device.

It is a block block diagram of the collision form discrimination | determination apparatus which concerns on the Example of this invention. It is a figure explaining operation | movement of the deceleration direction 1st amplitude level generation | occurrence | production count counter and the acceleration direction 1st amplitude level generation | occurrence | production count counter of the collision form discrimination device based on the Example of this invention. It is explanatory drawing of the collision form determination of the collision form determination apparatus based on the Example of this invention. 1 is a block configuration diagram of an occupant protection device according to an embodiment of the present invention. It is a figure explaining operation | movement of each amplitude level generation | occurrence | production count means of the passenger | crew protection apparatus which concerns on the Example of this invention. It is a figure explaining the subject of the conventional passenger protection device (two-stage type air bag device).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Collision form discrimination | determination apparatus 2 Acceleration sensor 3,30 Collision form determination part 4 Airbag expansion | deployment determination means 5 Airbag expansion | deployment drive means 6 Airbag apparatus 11 LPF (low-pass filter)
12 A / D converter 13 Count start control means 14 Acceleration direction first amplitude level occurrence count counting means 15 Deceleration direction first amplitude level occurrence count counting means 16 Collision form determination means 20 Crew protection device 21 Deceleration direction second amplitude level generation Number counting means 22 Decreasing direction third amplitude level occurrence number counting means 23 Airbag first stage deployment command generating means 24 Frontal collision airbag second stage deployment command generating means 25 Non-frontal collision airbag second stage deployment command generating Means 51 First stage ignition circuit 52 Second stage ignition circuit 61 First stage inflator 611 First stage squib 62 Second stage inflator 621 Second stage squib + Gs Collision detection threshold −L1 Acceleration direction amplitude determination threshold (acceleration Direction first amplitude level)
+ L1 Deceleration direction amplitude judgment threshold (Deceleration direction first amplitude level)
+ L2 Airbag first stage deployment judgment reference threshold + L3 Airbag second stage deployment judgment reference threshold

Claims (2)

An acceleration sensor for detecting the longitudinal acceleration of the vehicle;
The collision type of the vehicle is a frontal collision or non-frontal collision (offset collision, diagonal collision, etc.) based on whether the amplitude of the detection output signal of the acceleration sensor is in both the deceleration direction and the acceleration direction or mainly in the deceleration direction. A collision type determination apparatus comprising: a collision type determination unit that determines whether or not An acceleration sensor for detecting the longitudinal acceleration of the vehicle;
Counting start control means for generating a counting start command when acceleration in the deceleration direction detected by the acceleration sensor exceeds a preset collision detection threshold;
An acceleration direction first amplitude level occurrence number counting means for counting the number of occurrences of acceleration direction amplitude exceeding a preset acceleration direction amplitude determination threshold value from the time when the counting start command is generated;
A decelerating direction first amplitude level occurrence number counting means for counting the number of times of decelerating direction amplitude exceeding a preset decelerating direction amplitude determination threshold from the time when the counting start command is generated;
A deceleration direction second amplitude level occurrence count counting means for counting the number of occurrences of an amplitude exceeding a preset airbag first stage deployment determination reference threshold from the time when the counting start command is generated;
The number of occurrences of an amplitude that is larger than the airbag first stage deployment determination reference threshold and exceeds a preset airbag second stage deployment determination reference threshold from the time when the counting start command is generated. An acceleration direction third amplitude level generation number counting means for counting;
Based on the count value of the acceleration direction first amplitude level occurrence count counting means and the count value of the deceleration direction first amplitude level occurrence count counting means, the vehicle collision mode is a frontal collision or non-frontal collision (offset collision, A collision type determination means for determining whether the collision is an oblique collision,
An airbag first-stage deployment command is generated for generating an airbag first-stage deployment command when the count value of the deceleration direction second amplitude level generation number counting means reaches a preset first-stage airbag deployment threshold value. Means,
Front collision air for generating an airbag second stage deployment command when the count value of the deceleration direction third amplitude level occurrence number counting means reaches a preset second airbag deployment threshold value for a frontal collision. Bag second stage deployment command generation means;
Non-frontal collision that generates an airbag second-stage deployment command when the count value of the deceleration direction third amplitude level occurrence number counting means reaches a preset second-stage deployment threshold value of airbag for non-frontal collision Air bag second stage deployment command generating means;
Airbag deployment that ignites the first stage inflator of the airbag device based on the airbag first stage deployment command and ignites the second stage inflator of the airbag device based on the airbag second stage deployment command An occupant protection device comprising drive means.

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