JP6519451B2 - Air bag device - Google Patents

Description

  The present invention relates to an airbag device.

  Patent Document 1 below discloses an airbag apparatus in which the deployment pressure of the airbag is controlled in accordance with the physical size of the occupant and the distance between the occupant and the airbag.

JP 2001-278002 A

  However, the patent document 1 does not describe the timing of deployment of the air bag, that is, changing the timing at which gas is supplied into the air bag according to the distance between the occupant and the air bag.

  An object of the present invention is to obtain an air bag apparatus capable of changing the timing at which gas is supplied into the air bag according to the distance between the occupant and the air bag, in consideration of the above fact.

The air bag apparatus according to claim 1 is disposed on the front side of a gas generator generating gas when activated and an occupant seated on a seat of a vehicle, and the gas generated by the gas generator is contained therein. A distance detection unit that detects a distance between an airbag that is expanded from a stored state to a deployed state by being supplied, a distance between the occupant and a restraint surface of the airbag that is in a deployed state, and the distance detection unit detects when the distance is less than a predetermined distance, and a hydraulic device for actuating the gas generator at an earlier timing than when the detected distance exceeds the predetermined distance, the actuating device, from the passenger When the load detected by the load sensor that detects the load input to the seat is equal to or less than a predetermined load, the timing is faster than when the detected load exceeds the predetermined load. In actuating the gas generator.

  According to the air bag device of the first aspect, when the gas generator is operated by the actuating device, the gas generator generates the gas. Then, the gas generated by the gas generator is supplied to the inside of the airbag, whereby the airbag is expanded from the stored state to the deployed state. That is, the air bag is inflated on the front side of the occupant seated in the seat of the vehicle.

Here, in the airbag device according to claim 1, the distance between the occupant seated on the seat of the vehicle and the restraining surface of the airbag in the fully deployed state (hereinafter simply referred to as "the occupant / airbag distance") Is detected by Then, when the distance between the occupant and the air bag is equal to or less than the predetermined distance, the gas generator is activated at an earlier timing than when the predetermined distance is exceeded. Thus, the airbag can be inflated early when the distance between the occupant and the airbag is equal to or less than the predetermined distance. That is, when the occupant is seated near the airbag, the airbag can be inflated early.
Further, according to the air bag device of the first aspect, when the load detected by the load sensor is equal to or less than a predetermined load, the gas generator is activated at an earlier timing than when the predetermined load is exceeded. . Thus, the airbag can be inflated early if the load input from the occupant to the seat is less than the predetermined load, that is, if the occupant seated on the seat is less than the predetermined weight.

  The airbag apparatus according to claim 2 is the airbag apparatus according to claim 1, wherein the actuating apparatus is determined by the collision prediction device provided in the vehicle that the collision of the vehicle is unavoidable. The gas generator is operated earlier than usual.

  According to the air bag device of the second aspect, when it is determined that the collision of the vehicle is inevitable by the collision prediction device, the gas generator is activated at a timing earlier than the normal time. Thereby, when it is judged that collision of a vehicle is unavoidable, an air bag can be inflated early.

  The airbag apparatus according to claim 3 is the airbag apparatus according to claim 1 or 2, wherein the distance detection unit detects a position of the seat in the vehicle longitudinal direction, and the sheet position sensor And a calculation unit that calculates the distance between the occupant and the restraint surface of the airbag in the fully deployed state based on the position of the seat detected by the control unit.

  According to the airbag apparatus of the third aspect, the calculation unit calculates the distance between the occupant and the restraint surface of the airbag in the fully deployed state based on the position of the seat detected by the seat position sensor. Thus, the distance between the occupant and the air bag can be easily detected.

  The airbag apparatus according to the present invention has an excellent effect that the timing at which gas is supplied into the airbag can be changed according to the distance between the occupant and the airbag.

BRIEF DESCRIPTION OF THE DRAWINGS It is a side view which shows the cabin provided with the airbag apparatus of this embodiment. It is a side view which shows typically the state which the vehicle provided with the airbag apparatus described in FIG. 1 is drive | working toward the barrier for collision tests. It is a flowchart for demonstrating the method to operate a gas generator. It is an explanatory view for explaining a difference of time from a collision start by a difference of a physique or a collision form to a crew member's restraint end by an air bag.

First Embodiment
An airbag apparatus according to a first embodiment of the present invention will be described using FIGS. 1 to 4. In addition, arrow FR and arrow UP which are shown in the figure have shown the front direction (traveling direction) of a vehicle, and upper direction, respectively. Also, hereinafter, when the description is simply made using the front and rear, left and right, and up and down directions, unless otherwise noted, the front and rear directions of the vehicle, the left and right of the vehicle left and right direction (vehicle width direction), and the up and down directions of the vehicle I assume.

  As shown in FIG. 1, the airbag device 10 according to the present embodiment includes an airbag 14 stored in a folded state in a wheel pad provided at a central portion of a steering wheel 12, and an airbag 14. And a gas generator 16 for supplying a gas. In addition, the airbag device 10 detects a collision (front collision) of the vehicle 22 (see FIG. 2) with the seat position sensor 20 as a distance detection unit that detects the front-rear position of the seat 18. And an air bag ECU 24 as a distance detection unit and a calculation unit.

  The air bag 14 is formed in the shape of a bag in which the portion of the gas generator 16 into which the gas flows is opened. A state in which the air bag 14 is folded into a predetermined shape and stored in the wheel pad at the central portion of the steering wheel 12 is referred to as a "stored state", and a state in which the air bag 14 is inflated into a predetermined shape Is referred to as "the deployment complete state".

  The gas generator 16 includes a gas generating agent and an ignition mechanism for igniting the gas generating agent. By igniting the gas generating agent, it is possible to generate a high pressure gas instantaneously. Then, the high pressure gas generated by the gas generator 16 is supplied to the inside of the air bag 14 so that the air bag 14 is expanded from the storage state to the deployment completion state between the steering wheel 12 and the occupant P. .

  The seat position sensor 20 is, for example, a resistance type sensor, and the seat position sensor 20 is connected to a seat rail 26 that slidably supports the seat 18 in the front-rear direction. The resistance value of the seat position sensor 20 is changed by sliding the seat 18 in the front-rear direction. By matching the resistance value with the position of the seat 18 in the front-rear direction, it is possible to detect the position of the seat 18 in the front-rear direction. Further, based on the position in the front-rear direction of the seat 18 detected by the seat position sensor 20, the airbag ECU 24 determines the distance between the occupant P (head) and the restraint surface 14A of the airbag 14 in the unfolded state Calculate “Occupant / airbag distance L”). The air bag ECU 24 calculates the distance L between the occupant and the air bag on the assumption that the occupant's body shape corresponding to the position of the seat 18 in the front-rear direction. Also, the position of the seat 18 may be detected by a sensor other than the resistance type sensor.

  The airbag ECU 24 operates the gas generator 16 when a front collision of the vehicle is detected. Specifically, the acceleration sensor 30 and the vehicle speed sensor 32 are connected to the air bag ECU 24. Then, the airbag ECU 24 determines the level of the collision based on the signals input from the acceleration sensor 30 and the vehicle speed sensor 32. Further, when the air bag ECU 24 determines that the air bag 14 needs to be expanded, the air bag ECU 24 operates the gas generator 16 (the ignition mechanism of the gas generator 16 is energized). In the present embodiment, when the speed of the vehicle 22 detected by the vehicle speed sensor 32 is equal to or higher than a predetermined speed, the integrated value of the acceleration detected by the acceleration sensor 30 (obtained by integrating the acceleration over time) The air bag ECU 24 operates the gas generator 16 when the value (a) exceeds a predetermined threshold value. In the present embodiment, as the threshold of the integrated value of the acceleration detected by the acceleration sensor 30, the “normal threshold” and the “sensitive threshold” which is a smaller value than the normal threshold are provided. Then, by switching between the “normal threshold (first threshold)” and the “sensitivity threshold (second threshold)”, the operation timing of the gas generator 16 at the time of a collision is switched. As a result, when the "sensitivity threshold" is selected, the operation timing of the gas generator 16 is advanced earlier than when the "normal threshold" is selected.

  Specifically, when the occupant / airbag distance L detected by the seat position sensor 20 and the airbag ECU 24 is equal to or less than a predetermined distance, the “sensitive threshold” is selected and exceeds the predetermined distance. “Normal threshold” is selected. In addition, the above-mentioned predetermined distance is an occupant / when the AF 05 dummy (a small-sized dummy among US adult women) for a collision test sits on the seat 18 set in the posture and position determined in the collision test. It is the distance L between air bags.

(Operation and effect of the present embodiment)
Next, the operation and effects of the present embodiment will be described.

  As shown in FIGS. 1 and 2, the occupant P is seated on the seat 18 and slides the seat 18 in the front-rear direction to change the seating position. In addition, when the occupant P is driving the vehicle 22 and the vehicle 22 collides with the obstacle 34 at a predetermined speed or more, the airbag 14 is instantly inflated to the deployed state. Thus, the head of the occupant P, which has been moved to the front side by inertia, is received by the airbag 14, and kinetic energy of the occupant P is absorbed by the airbag 14. The gas in the air bag 14 is gradually discharged through a vent hole (not shown).

  Here, in the present embodiment, the operation timing of the gas generator 16 for supplying the gas into the air bag 14 is switched by the air bag ECU 24 according to the procedure shown in the flowchart of FIG. 3. Specifically, the air bag ECU 24 first determines in step S1 whether the vehicle 22 has collided. The determination as to whether the vehicle 22 has collided is made based on the acceleration detected by the acceleration sensor 30. If a negative determination is made in step S1 (if it is determined that the vehicle 22 has not collided), the airbag ECU 24 determines the threshold for operating the gas generator 16 (the integrated value of the acceleration detected by the acceleration sensor 30) The “normal threshold” is selected and maintained.

  If an affirmative determination is made in step S1 (if it is determined that the vehicle 22 has collided), the airbag ECU 24 determines the severity of the collision in step S2. The determination of the severity of the collision is made based on the speed of the vehicle 22 detected by the vehicle speed sensor 32. That is, if the speed of the vehicle 22 is a high speed exceeding a predetermined speed, it is determined that the severity of the collision is high, and if the speed of the vehicle 22 is a low speed below the predetermined speed, the collision is It is judged that the severity is low. If a negative determination is made in step S2 (if it is determined that the severity of the collision is low), the airbag ECU 24 maintains the state in which the "normal threshold" is selected.

  Furthermore, if an affirmative determination is made in step S2 (if the severity of the collision is determined to be high), the airbag ECU 24 determines the collision type in step S3. The determination of the collision type is made based on the waveform of the acceleration detected by the acceleration sensor 30 or the like. That is, when the rising of the waveform of the acceleration (deceleration acceleration) detected by the acceleration sensor 30 is rapid, it is determined that the collision is a front collision (full wrap collision), and the rising of the waveform of the acceleration detected by the acceleration sensor 30 Is determined to be a collision other than a frontal collision (for example, a diagonal collision). If a negative determination is made in step S3 (if it is determined that the collision is a collision other than a frontal collision), the airbag ECU 24 maintains the state in which the “normal threshold value” is selected.

  If the determination in step S3 is affirmative (if it is determined that there is a frontal collision), the airbag ECU 24 determines the physique of the occupant P seated on the seat 18 in step S4. The determination of the physical size of the occupant P seated on the seat 18 is made based on the occupant / airbag distance L (the seating position of the occupant P) detected by the seat position sensor 20 and the airbag ECU 24. That is, when the occupant / airbag distance L is equal to or less than a predetermined distance, it is determined that the physical size of the occupant P seated on the seat 18 is small, and the occupant / airbag distance L exceeds the predetermined distance. It is determined that the physical size of the occupant P seated on the seat 18 is large. Then, if an affirmative determination is made in step S4 (judged that the physical size of the occupant P is small), the airbag ECU 24 determines the threshold value for operating the gas generator 16 (the integrated value of the acceleration detected by the acceleration sensor 30). Switch from “normal threshold” to “sensitive threshold”. Further, when the integrated value of the acceleration detected by the acceleration sensor 30 reaches the “sensitive threshold value”, the airbag ECU 24 operates the gas generator 16. As a result, the gas generated by the gas generator 16 is supplied into the air bag 14, and the air bag 14 is instantly inflated from the stored state to the deployed state. On the other hand, if a negative determination is made in step S4 (judged that the physical size of the occupant P is large), the airbag ECU 24 maintains the state in which the "normal threshold" is selected. Then, when the integrated value of the acceleration detected by the acceleration sensor 30 reaches the “normal threshold value”, the airbag ECU 24 operates the gas generator 16. As a result, the gas generated by the gas generator 16 is supplied into the air bag 14, and the air bag 14 is instantly inflated from the stored state to the deployed state.

  As described above, in the airbag device 10 of the present embodiment, as shown in FIG. 4, the small passenger P expected to be seated at a position closer to the steering wheel 12 compared with the large passenger P has a seat When seated at 18, the gas generator 16 for supplying gas into the air bag 14 can be activated early. As a result, the small-sized passenger P can be restrained earlier by the airbag 14 as compared with the large-sized passenger P. The large passenger P is a large-sized passenger including the AM 50 dummy (a dummy of an average shape of an adult male in the United States) for a collision test. Further, a code T0 is a time when the vehicle 22 starts a collision with the obstacle 34, and a code T1 is a time when the gas generator 16 operates. Reference T2 is the time when the occupant starts to be restrained by the airbag 14 (time when gas in the airbag 14 starts to be discharged through the vent hole), and T3 is the time when restraint of the occupant P by the airbag 14 is finished. It is.

  In the lower part of FIG. 4, as a reference example, the gas generator 16 in the case where the vehicle 22 collides obliquely with the obstacle 34 (slant collision) or when the vehicle 22 collides with the obstacle 34 in an offset collision (ODB collision) Is shown at time T1 when it was activated. As shown in this figure, in the collision mode, the rising of the waveform of the acceleration detected by the acceleration sensor 30 is gentler than that in the full lap collision. Therefore, the time (the time from T0 to T1) until the integrated value of the acceleration detected by the acceleration sensor 30 reaches the “normal threshold” is longer than in the case of the full wrap collision.

  In addition, as shown in FIG. 1, in the present embodiment, an example in which the “normal threshold” and the “sensitive threshold” are switched based on a signal input from the seat position sensor 20 to the airbag ECU 24 However, the present invention is not limited thereto. For example, in addition to detecting the longitudinal position of the seat 18 based on a signal input from the seat position sensor 20 to the airbag ECU 24, a signal input from the load sensor 36 provided on the seat 18 to the airbag ECU 24 may be used. It can also be configured to switch between the “normal threshold” and the “sensitive threshold” based on that. More specifically, if the load detected by the load sensor 36 for detecting the load input to the seat 18 from the occupant P seated on the seat 18 is equal to or less than the predetermined load, the “sensitive threshold” is selected, If the predetermined load is exceeded, the "normal threshold" is selected. The above-mentioned predetermined load refers to the case where the occupant P of the same shape as the dummy (a small-sized female dummy) of AF 05 for a collision test is seated on the seat 18 set in the posture or the like determined in the collision test. The load is detected by the load sensor 36. The load sensor 36 is a sheet-like pressure sensor provided on the seat cushion 18B. In the configuration described above, the physique of the occupant P seated on the seat 18 can be determined based on the signals from the two sensors (the seat position sensor 20 and the load sensor 36). The configuration is useful when applied to a front passenger seat where it may be possible for the small passenger P to be seated on the seat 18 with the seat 18 positioned rearward.

Second Embodiment
Next, an airbag device 10 according to a second embodiment of the present invention will be described.

  As shown in FIG. 2, the airbag apparatus 10 according to the present embodiment uses “normal threshold” and “sensitive threshold” based on a signal input from the collision prediction apparatus 38 provided in the vehicle 22 to the airbag ECU 24. Is characterized by being switched.

  Specifically, when it is determined that the collision of the vehicle 22 is inevitable by the collision prediction device 38, the “sensitive threshold” is selected, and it is determined that the collision of the vehicle 22 is not inevitable. In the case (normal time), "normal threshold" is selected. More specifically, as shown in FIG. 2, the collision prediction device 38 is configured to include a collision prediction ECU 40, a millimeter wave radar 42, a camera 44 and the like. The millimeter wave radar 42 is provided at the front end of the vehicle 22 (for example, a grill or the like). By transmitting radio waves from the millimeter wave radar 42 to the obstacle 34 on the front side of the vehicle and receiving a reflected wave from the obstacle 34, the distance from the vehicle 22 to the obstacle 34 and the vehicle 22 and the obstacle 34 It is possible to measure the relative velocity of In addition, the camera 44 is provided on the inner side (cabin side) of the front windshield glass of the vehicle 22. The camera 44 photographs the front side of the vehicle, and by analyzing the image photographed by the camera 44, it is possible to measure the shape and size of the obstacle 34 on the front side of the vehicle 22. It has become. When the collision prediction ECU 40 determines that the collision of the vehicle 22 with the obstacle 34 is inevitable based on the information obtained from the millimeter wave radar 42 and the camera 44, the airbag ECU 24 receives the collision from the collision prediction ECU 40. A switching signal from “normal threshold” to “sensitive threshold” is output. In this configuration, the threshold value of the integrated value of the acceleration detected by the acceleration sensor 30 in advance can be changed from the “normal threshold value” to the “sensitive threshold value” before the vehicle 22 collides.

  As mentioned above, although one embodiment of the present invention was described, the present invention is not limited to the above, and can be variously modified and carried out in addition to the above in the range which does not deviate from the main point. Of course.

10 Air bag device 14 Air bag 14A Restraint surface 16 Gas generator 18 Seat 20 Seat position sensor (distance detection unit)
22 Vehicle 24 Airbag ECU (Activator, Distance Detection Unit and Calculation Unit)
36 load sensor 38 collision prediction device

Claims (3)

A gas generator that generates gas by being operated;
An air bag disposed on the front side of an occupant seated on a seat of a vehicle and inflated from a stored state to a deployed state by the gas generated by the gas generator being supplied therein.
A distance detection unit that detects a distance between the occupant and a restraint surface of the airbag in a fully deployed state;
An operating device that operates the gas generator at an earlier timing than when the detected distance exceeds the predetermined distance when the distance detected by the distance detection unit is equal to or less than the predetermined distance;
Equipped with
When the load detected by the load sensor that detects the load input from the occupant to the seat is equal to or less than a predetermined load, the actuating device is faster than when the detected load exceeds the predetermined load. The airbag apparatus which operates the said gas generator at a timing .   2. The gas generator according to claim 1, wherein the actuating device operates the gas generator at a timing earlier than a normal time when it is determined that a collision of the vehicle is inevitable by a collision prediction device provided in the vehicle. Airbag device. The distance detection unit
A seat position sensor that detects the position of the seat in the vehicle longitudinal direction;
A calculation unit that calculates the distance between the occupant and the restraint surface of the airbag in the unfolded state based on the position of the seat detected by the seat position sensor;
The air bag device according to claim 1 or claim 2, comprising: