JP6520653B2 - Vehicle airbag system - Google Patents

Description

  The present invention relates to a vehicle airbag system.

  The airbag apparatus described in Patent Document 1 includes an airbag that is inflated in front of a passenger by a deployment gas, and a volume control tether that is provided outside the airbag and that the volume inside the airbag during deployment is a predetermined value or less. And have. Further, the air bag device includes a capacity setting information acquiring unit for acquiring information on at least one of a group consisting of a position, a physical size, a weight, and a magnitude of an impact due to a collision, and a capacity regulation according to the information. The tether release means includes a tether release means for releasing the proximal end of the tether, and a variable vent means which is opened prior to the operation of the tether release means and closed in conjunction with the operation of the tether release means. Thus, even when the position, physical size, weight, etc. of the occupant are different, the occupant is appropriately restrained.

JP, 2009-298222, A

  By the way, in a vehicle equipped with an automatic brake called a collision damage reduction brake or the like, the automatic brake operates just before a frontal collision. Therefore, when the occupant in the front seat, whose seating position is relatively on the front side, inertially moves forward by braking the vehicle, the distance between the interior part (steering wheel or instrument panel) in which the airbag is stored and the occupant in the front seat And may prevent smooth deployment of the airbag.

  In view of the above facts, the present invention makes the air bag smooth even when the distance between the interior part storing the air bag and the front passenger becomes short due to the forward movement of the front passenger by braking of the vehicle just before a frontal collision. It is an object of the present invention to provide a vehicle air bag system that can be deployed in

  The vehicle airbag system according to the present invention is accommodated in an interior part positioned in front of a front seat occupant of the vehicle, and when the vehicle collides in the front, the front seat occupant and the interior part are An airbag that inflates and deploys in between, a strap attached to the airbag limits expansion of the airbag in the front-rear direction of the vehicle, and an expansion limiting portion capable of releasing the limitation, the front seat occupant for the vehicle The vehicle immediately before a frontal collision using the occupant position detection unit for detecting the position of the vehicle, the braking condition detection unit for detecting the braking condition of the vehicle, and the detection results of the occupant position detection unit and the braking condition detection unit. Estimate the distance between the front-seat occupant and the interior part after inertial movement to the front side by braking the vehicle, and release the restriction when the distance is equal to or greater than a reference value, while the distance is the reference And and a control device for maintaining the limit in the case of less than.

  According to the first aspect of the present invention, the air bag is accommodated in the interior part located in front of the front passenger of the vehicle. This air bag inflates and deploys between the front passenger and the above-mentioned interior parts when a frontal collision of the vehicle occurs. The airbag has an expansion limiting strap attached thereto. The expansion restricting portion restricts the expansion of the airbag in the vehicle longitudinal direction by the above-mentioned strap and is capable of releasing the restriction.

  Further, in the present invention, the occupant position detection unit detects the position of the front seat occupant with respect to the vehicle, and the braking condition detection unit detects the braking condition of the vehicle. Then, using the detection results of the occupant position detection unit and the braking state detection unit, the control device estimates the distance between the front passenger and the interior parts after the inertia movement to the front side by the braking of the vehicle just before the frontal collision. Do. When the estimated distance is equal to or greater than the reference value, that is, when it is estimated that the distance between the front passenger and the interior part is long, the control device cancels the restriction of the expansion limiting unit. As a result, the air bag inflates and deploys without being restricted in the longitudinal expansion of the vehicle. On the other hand, when the estimated distance is less than the reference value, that is, when it is estimated that the distance between the front seat passenger and the interior part is short, the control device causes the expansion limiting unit to maintain the above limitation. As a result, the air bag is inflated and deployed while the expansion in the longitudinal direction of the vehicle is limited. Therefore, the airbag can be smoothly deployed even when the distance between the front passenger and the interior parts becomes short due to braking of the vehicle immediately before the frontal collision.

  The vehicle air bag system according to a second aspect of the present invention is the vehicle air bag system according to the first aspect, wherein the interior part is a steering wheel whose position relative to the vehicle can be adjusted, and detects the position of the steering wheel relative to the vehicle The control device further includes a steering position detection unit, and the control device uses a detection result of the steering position detection unit when estimating the distance.

  According to the second aspect of the present invention, the steering wheel positioned in front of the front passenger is adjustable in position with respect to the vehicle, and the position of the adjusted steering wheel is detected by the steering position detector. The detection result is used when the control device estimates the distance between the front passenger and the steering wheel. Thereby, even when the steering wheel is position-adjusted, the accuracy of the distance estimated by the control device can be secured.

The vehicle air bag system according to the invention of claim 3 is the vehicle air bag system according to claim 1 or 2, wherein the occupant position detection unit is based on a seat slide position of a front seat at which the front seat occupant is seated. A seat slide sensor for detecting the position of the front seat occupant with respect to the vehicle, and the braking condition detection unit is an acceleration sensor for detecting the braking condition based on acceleration in the longitudinal direction of the vehicle generated on the floor of the vehicle; In the device, the seat slide position is on the front side of the vehicle with respect to a preset position, and the amount of the inertial movement calculated by time integration of the acceleration immediately before the frontal collision is equal to or greater than a preset amount. , it estimated that the distance is less than the reference value.

According to the third aspect of the present invention, the control device is configured such that the seat slide position detected by the seat slide sensor is on the vehicle front side relative to the preset position and the acceleration detected by the acceleration sensor immediately before a frontal collision of the vehicle. If the amount of inertial movement of the front seat passenger calculated by time integration is equal to or greater than a preset amount, it is estimated that the distance between the front seat passenger and the interior part after the inertial movement is less than (close to) the reference value. As a result, it is possible to perform estimation (determination) as to whether or not the distance between the front seat passenger and the interior part is short, by simple control.
The vehicle air bag system according to the invention described in claim 4 is the vehicle airbag system according to any one of claims 1 to 3, wherein the braking status detection unit generates the vehicle floor in the front-rear direction near the center of the vehicle. It is a floor G sensor that detects acceleration.
The vehicle air bag system according to the invention as set forth in claim 5 is the vehicle air bag system according to any one of claims 1 to 4, wherein the expansion limiting portion is disposed in the air bag and one end thereof is the air. The pair of upper and lower straps fixed to the tip of the bag and the proximal end of the airbag are accommodated in the airbag, and the other ends of the pair of upper and lower straps are engaged and operated. A pair of upper and lower actuators for releasing the engagement, and the control device operates the pair of upper and lower actuators when the distance is equal to or greater than a reference value, and the upper side when the distance is less than the reference value While the lower actuator is not operated.

  As described above, in the vehicle air bag system according to the present invention, the distance between the interior parts storing the air bag and the front passenger becomes short due to the forward movement of the front passenger by braking of the vehicle just before a frontal collision. Even in this case, the airbag can be deployed smoothly.

It is a typical side view showing the composition of the case front of a vehicle to which the air bag system for vehicles concerning a 1st embodiment of the present invention was applied, and expansion restriction of the air bag by expansion restriction part is maintained, and air It is a figure which shows the state which the bag expanded and expanded. FIG. 8 is a side view corresponding to FIG. 1 showing a state in which the expansion restriction of the air bag by the expansion restriction portion is released and the air bag is expanded and deployed. It is a block diagram showing the composition of the air bag system for the vehicles. It is a flowchart which shows the control procedure of the airbag system for the said vehicles. FIG. 6 is a side view corresponding to FIG. 1 showing a configuration of a front portion of a cabin to which a vehicle airbag system according to a second embodiment of the present invention is applied.

First Embodiment
Hereinafter, a vehicle airbag system 10 according to a first embodiment of the present invention will be described using FIGS. 1 to 4. Arrows FR appropriately shown in the respective drawings indicate the forward direction (traveling direction) of the vehicle 12 to which the vehicle airbag system 10 is applied, and the arrow UP indicates the upward direction of the vehicle 12. Hereinafter, in the case where the description is simply made using the front and rear direction and the upper and lower direction, the front and rear direction of the vehicle and the upper and lower direction of the vehicle are shown unless otherwise noted.

(Constitution)
As shown in FIGS. 1 to 3, the vehicle airbag system 10 includes a driver seat airbag device 14, an expansion limiting unit 16, a seat slide sensor 18 as an occupant position detection unit, and a control device 20. Is equipped. As shown in FIG. 3, the control device 20 is configured of an airbag ECU 22, a collision detection sensor 24, and a collision prediction sensor 26. In addition, the air bag ECU 22 is configured to include a floor G sensor 28 as an acceleration sensor (a braking status detection unit). Hereinafter, each component described above will be described.

  The driver seat airbag device 14 is mounted on a center pad portion 30A provided at the center of the steering wheel 30 located in front of an occupant (front occupant) P seated in the driver seat (front seat) 13 of the vehicle 12 It is done. The driver's seat airbag device 14 includes an airbag 32 and an inflator 34 which is a gas generator. The air bag 32 is formed in a bag shape by sewing a plurality of base cloths formed by cutting out a nylon or polyester cloth material, for example. The air bag 32 is usually housed in the center pad portion 30A in a folded state. In addition, in FIG. 1 and FIG. 2, the code | symbol 15 is attached to the instrument panel.

  The inflator 34 is fixed in the center pad portion 30A, and has a gas injection portion inserted into the air bag 32 via a gas supply port formed in the air bag 32. When the inflator 34 is activated (activated), gas is ejected from the gas ejection portion into the air bag 32. Thus, the airbag 32 is configured to be inflated and deployed between the occupant P and the steering wheel 30 (see FIGS. 1 and 2). In the steering wheel 30, the center pad portion 30A does not rotate relative to the steering column 31, and the grip portion (rim portion) 30B rotates relative to the center pad portion 30A. It is considered to be a rotating type.

  The expansion limiting unit 16 includes a plurality of (here, upper and lower pairs) straps 36 and 38 and a plurality of (here, upper and lower pairs) actuators 40 and 42. The pair of upper and lower straps 36 and 38 are formed by cutting a cloth material similar to the base cloth of the air bag 32 into a band shape, and is disposed in the air bag 32. One end of each of the straps 36 and 38 is fixed to the front end side (rear end side in the inflated and deployed state) of the air bag 32 by means such as sewing.

  The pair of upper and lower actuators 40 and 42 are accommodated in the air bag 32 on the base end side of the air bag 32, and fixed to the center pad portion 30A. The actuators 40, 42 are provided with engaging members such as hooks engaged with the other ends of the straps 36, 38, respectively. Each of the actuators 40 and 42 is, for example, an actuator using a gas generator or an electrical actuator such as a solenoid. When each actuator 40, 42 is actuated (activated), the above-mentioned engaging member is deformed or displaced, and the engagement between each actuator 40, 42 and the other end of each strap 36, 38 is released. There is.

  As shown in FIG. 1, when each of the actuators 40 and 42 is not activated at the time of inflation and deployment of the airbag 32, the airbag 32 is inflated while the expansion in the vehicle longitudinal direction is limited (suppressed) by the pair of straps 36 and 38. expand. On the other hand, as shown in FIG. 2, when each of the actuators 40 and 42 is actuated at the time of inflation and deployment of the airbag 32, the airbag 32 inflates and deploys without being subjected to the above-described inflation restriction by the pair of straps 36 and 38. Do. When the air bag 32 receives the above-described expansion restriction, the expansion thickness of the air bag 32 in the front-rear direction of the vehicle is smaller than in the case where the expansion restriction is not received. The pair of straps 36 and 38 and the pair of actuators 40 and 42 may be disposed outside the airbag 32 instead of being disposed inside the airbag 32. Further, the configuration of the expansion limiting unit 16 is merely an example, and can be changed as appropriate.

  A seat slide sensor 18 which is an occupant position detection unit is attached to a seat slide rail 46 provided at the lower end portion of the driver's seat 13. The seat slide sensor 18 determines the position of the head H of the occupant P relative to the vehicle 12 based on the seat slide position of the driver's seat 13, ie, the position before and after the driver's seat 13 relative to the vehicle 12 (hereinafter simply referred to as "position of the occupant P"). Is sometimes configured to detect.

  In the present embodiment, the occupant position detection unit is configured only by the seat slide sensor 18, but the present invention is not limited to this. For example, the occupant position detection unit may be at least one of the seatback angle sensor 54, the seatback capacitance sensor 56, the seat cushion load sensor 58, the seat leg load sensors 60, 62, etc. shown by imaginary lines in FIG. And the seat slide sensor 18 may be combined.

  The above-mentioned seat back angle sensor 54 is provided in the vicinity of the connecting portion between the seat cushion 13A of the driver's seat 13 and the seat back 13B, and detects the reclining angle of the seat back 13B with respect to the seat cushion 13A. By combining the seat back angle sensor 54 with the seat slide sensor 18, the position of the driver's seat 13 relative to the vehicle 12 can be detected more accurately.

  The seat back capacitance sensor 56, the seat cushion load sensor 58, and the seat leg load sensors 60 and 62 detect the position of the occupant P relative to the driver's seat 13. Specifically, the seat back capacitance sensor 56 is provided on the seat back 13B, and detects the distance between the back of the occupant P and the seat back 13B based on the change in capacitance. The seat cushion load sensor 58 also detects the distribution of the load that the seat cushion 13A receives from the occupant P. The seat leg load sensors 60 and 62 are provided on the front and rear legs (brackets) 17 and 19 of the driver's seat 13 and detect the balance between the loads received by the legs 17 and 19. By adding at least one of these sensors to the occupant position detection unit, it is possible to detect the position of the occupant P relative to the vehicle 12 more accurately.

  Further, the occupant position detection unit may be an in-vehicle camera 64 shown by an imaginary line in FIG. 1, or the in-vehicle camera 64 and at least one of the above-described sensors are combined. It is also good. The in-vehicle camera 64 detects the position of the occupant P relative to the vehicle 12 from an image obtained by imaging the occupant P in the compartment 48, and directly detects the position of the occupant P relative to the vehicle 12. Therefore, even when the occupant position detection unit is configured only by the in-vehicle camera 64, the position of the occupant P can be detected with high accuracy.

  On the other hand, the airbag ECU 22 is attached to a floor tunnel (not shown) below the center console 50 disposed at the center in the vehicle width direction at the front of the compartment 48 and disposed near the center of the vehicle 12 There is. The air bag ECU 22 includes a control unit, a ROM, a RAM, an input / output interface, a drive circuit, and the like connected to one another via a bus. A control program is stored in the ROM. Then, the control unit executes the program stored in the ROM while using the temporary storage function of the RAM. Further, position information of the steering wheel 30 is stored in advance in the ROM. The floor G sensor 28 is incorporated in the air bag ECU 22.

  The floor G sensor 28 detects longitudinal acceleration (hereinafter referred to as longitudinal G) and lateral acceleration (hereinafter referred to as lateral G) generated on the floor 52 of the vehicle 12 near the center of the vehicle 12. The floor G sensor 28 is used to control the operation of the inflator 34. However, in the present embodiment, the floor G sensor 28 is also used as a braking condition detection unit that detects the braking condition (braking condition) of the vehicle 12. That is, since there is a correlation between the front and rear G occurring on the floor 52 and the braking state of the vehicle 12, the braking state of the vehicle 12 can be detected based on the front and rear G detected by the floor G sensor 28.

  In the present embodiment, although the floor G sensor 28 is used as the braking condition detection unit, the present invention is not limited to this. For example, the braking state detection unit may be the brake depression force sensor 66 shown by an imaginary line in FIG. 1, or the floor G sensor 28 and the brake depression force sensor 66 are combined and configured. It is also good. The brake depression force sensor 66 detects a load when the occupant P depresses the brake pedal 68. Since there is a correlation between this load and the braking condition of the vehicle 12, the braking condition of the vehicle 12 can be detected based on the load detected by the brake depression force sensor 66.

  As shown in FIG. 3, the inflator 34 described above, the pair of actuators 40 and 42, and the seat slide sensor 18 are electrically connected to the air bag ECU 22. Further, a collision detection sensor 24 and a collision prediction sensor 26 are electrically connected to the air bag ECU 22.

  The collision detection sensor 24 is formed of, for example, a pair of left and right front satellite sensors attached to the front end of the vehicle 12 and detects front and rear G generated in the front end of the vehicle 12 due to a frontal collision. The air bag ECU 22 calculates the output signal of the collision detection sensor 24 and determines the level of the collision together with the output signal of the floor G sensor 28. Then, when it is determined that the airbag ECU 22 needs to inflate and deploy the airbag 32, an actuation signal is output to the inflator 34.

  The collision prediction sensor (forward monitoring sensor) 26 includes, for example, at least one of a millimeter wave radar, a laser radar, a monocular camera, a stereo camera, an infrared camera, etc. Detect vehicles and obstacles. The collision prediction sensor 26 is also used as a component of an automatic braking system mounted on the vehicle 12. The automatic brake system includes an automatic brake ECU (not shown) mounted on the vehicle 12. The automatic brake ECU is configured to automatically operate the brakes of the vehicle 12 when it is determined that a frontal collision of the vehicle 12 is inevitable based on the output signal of the collision prediction sensor 26.

  Here, in the present embodiment, the airbag ECU 22 brakes the vehicle 12 immediately before a frontal collision, using detection results of the seat slide sensor 18 (occupant position detection unit) and the floor G sensor 28 (braking condition detection unit). The distance between the occupant P and the steering wheel 30 after the inertial movement to the front side according to. Specifically, the airbag ECU 22 uses the detection result of the floor G sensor 28 to move the inertial movement amount L of the occupant P to the front side with respect to the vehicle 12 immediately before the frontal collision (see FIGS. Estimate the quantity L). Then, the airbag ECU 22 estimates the distance between the occupant P after the forward movement and the steering wheel 30 using the estimation result and the detection result of the seat slide sensor 18 before the forward movement of the occupant P.

  Then, when the estimated distance is equal to or greater than a preset reference value, the airbag ECU 22 actuates the actuators 40, 42 when activating the inflator 34. On the other hand, when the estimated distance is less than the reference value, the air bag ECU 22 does not operate the actuators 40 and 42 when operating the inflator 34. Supplementing this estimation of the distance, the airbag ECU 22 is located on the vehicle front side (for example, near the front most position) than the position set in advance by the seat slide position detected by the seat slide sensor 18 and just before a frontal collision. If the inertial movement amount L calculated by time integration of the front and rear G detected by the floor G sensor 28 is equal to or more than a preset amount, it is estimated that the above distance is less than the reference value.

  Next, a specific control procedure of the vehicle airbag system 10 according to the present embodiment will be described with reference to the flowchart shown in FIG. This flowchart is performed, for example, in a state where the engine of the vehicle 12 is driven. First, in step S1, the airbag ECU 22 detects the position of the occupant P relative to the vehicle 12 based on the output signal of the seat slide sensor 18. When the process in step S1 is completed, the process proceeds to step S2.

  In step S2, the airbag ECU 22 determines whether a frontal collision of the vehicle 12 is unavoidable based on the output signal of the collision prediction sensor 26. If this determination is negative, the process returns to step S1 and the above-described process is repeated. On the other hand, when this determination is affirmed, it transfers to step S3.

  In step S3, the airbag ECU 22 estimates the forward movement amount L of the occupant P with respect to the vehicle 12 immediately before the frontal collision using the detection result of the floor G sensor 28. Specifically, the airbag ECU 22 integrates the front and back G detected by the floor G sensor 28 by the time from when it is determined that a frontal collision is inevitable to when the frontal collision is scheduled to occur, The amount of forward movement L described above is calculated. When the process in step S3 is completed, the process proceeds to step S4.

  In step S4, the airbag ECU 22 detects the position of the occupant P before the forward movement detected by the seat slide sensor 18 (see the occupant P shown by the two-dot chain line in FIGS. 1 and 2) and the forward movement amount L calculated above. The distance between the steering wheel 30 (SW) and the occupant P after forward movement (see the occupant P shown by solid lines in FIGS. 1 and 2) is estimated. When the process in step S4 is completed, the process proceeds to step S5.

  In step S5, the airbag ECU 22 compares the distance estimated in step S5 with a preset reference value. When the estimated distance is equal to or greater than the reference value, that is, when it is estimated that the distance between the occupant P and the steering wheel 30 is long, the airbag ECU 22 proceeds to step S6. On the other hand, when the estimated distance is less than the reference value, that is, when it is estimated that the distance between the occupant P and the steering wheel 30 is short, the airbag ECU 22 proceeds to step S8.

  In step S6, the airbag ECU 22 determines the level of the frontal collision based on the output signals of the collision detection sensor 24 and the floor G sensor 28. As a result, when it is determined that the airbag ECU 22 does not need to inflate and deploy the airbag 32, the process returns to step S1 and the above-described processing is repeated. On the other hand, if the air bag ECU 22 determines that the air bag 32 needs to be inflated and deployed, the process proceeds to step S7.

  In step S7, since it is estimated that the distance between the occupant P and the steering wheel 30 is long in step S5, the airbag ECU 22 operates the actuators 40 and 42 and the inflator 34. As a result, the airbag 32 is inflated and deployed in a state where the engagement between the other end of the straps 36 and 38 and the actuators 40 and 42 is released. In this case, the air bag 32 inflates and deploys without being subjected to the expansion limitation by the pair of straps 36 and 38 (see FIG. 2).

  On the other hand, when it is estimated that the distance between the occupant P and the steering wheel 30 is short in step 5 and the process proceeds to step S8, the same process as step S6 is performed. That is, in step S8, the air bag ECU 22 determines the level of the frontal collision based on the output signals of the collision detection sensor 24 and the floor G sensor 28. As a result, when it is determined that the airbag ECU 22 does not need to inflate and deploy the airbag 32, the process returns to step S1 and the above-described processing is repeated. On the other hand, when the air bag ECU 22 determines that the air bag 32 needs to be inflated and deployed, the process proceeds to step S9.

  In step S9, since it is estimated that the distance between the occupant P and the steering wheel 30 is short in step S5, the airbag ECU 22 operates the inflator 34 without operating the actuators 40 and 42. As a result, the airbag 32 is inflated and deployed in a state in which the engagement between the other ends of the straps 36 and 38 and the actuators 40 and 42 is maintained. In this case, the air bag 32 is inflated and deployed under the expansion limitation by the pair of straps 36 and 38 (see FIG. 1).

(Action and effect)
Next, the operation and effects of the first embodiment will be described.

  In the vehicle air bag system 10 configured as described above, the air bag 32 is housed in the steering wheel 30 of the vehicle 12. The airbag 32 inflates and deploys between the occupant P of the driver's seat 13 and the steering wheel 30 when the vehicle 12 makes a frontal collision. Straps 36 and 38 of the expansion limiting portion 16 are attached to the air bag 32. The expansion restricting portion 16 restricts the expansion of the air bag 32 in the longitudinal direction of the vehicle by the straps 36 and 38, and the restriction can be released.

  Further, in the vehicle airbag system 10, the seat slide sensor 18 detects the position of the occupant P relative to the vehicle 12, and the floor G sensor 28 detects the braking condition of the vehicle 12. Then, the airbag ECU 22 of the control device 20 estimates the forward movement amount L of the occupant P with respect to the vehicle 12 immediately before the frontal collision, using the detection result of the floor G sensor 28. Further, the airbag ECU 22 estimates the distance between the occupant P after the forward movement and the steering wheel 30 using the estimated forward movement amount L and the detection result of the seat slide sensor 18 before the forward movement of the occupant P. Do.

  Then, when the estimated distance is equal to or greater than the reference value, that is, when it is estimated that the distance between the occupant P and the steering wheel 30 is long, the airbag ECU 22 operates the actuators 40, 42 of the expansion limiting unit 16 to Let go. As a result, the air bag 32 inflates and deploys without being limited in its expansion in the longitudinal direction of the vehicle (see FIG. 2).

  On the other hand, when the estimated distance is less than the reference value, that is, when it is estimated that the distance between the occupant P and the steering wheel 3 is short, the air bag ECU 22 does not operate the actuators 40, 42 of the expansion limiting unit 16, and Maintain expansion limit. Thus, the air bag 32 is inflated and deployed in a state in which the expansion in the longitudinal direction of the vehicle is limited. Therefore, even when the distance between the occupant P and the steering wheel 30 becomes short due to the braking of the vehicle 12 immediately before the frontal collision, the airbag 32 can be smoothly deployed. Moreover, it also contributes to the prevention or suppression of the occupant P receiving a load from the air bag 32 during the inflation and deployment.

  Further, in the present system 10, the airbag ECU 22 is configured such that the seat slide position detected by the seat slide sensor 18 is on the vehicle front side relative to the preset position and the calculated forward movement amount L is greater than the preset amount. In this case, it is estimated that the distance between the occupant P and the steering wheel 30 after forward movement is less than (closer to) the reference value. Thereby, it is possible to estimate (determine) whether the distance between the occupant P and the steering wheel 30 is short or not by simple control.

Further, in the present system 10, an occupant position detection unit that detects the position of the occupant P relative to the vehicle 12 is a seat slide sensor 18 that detects a seat slide position of the driver's seat 13. Thus, for example, the seat slide sensor 18 mounted on the vehicle 12 as a standard together with the driver seat airbag device 14 can be used as an occupant position detection unit. Similarly, in the present system 10, a braking status detection unit that detects a braking status of the vehicle 12 is a floor G sensor 28 that detects front and rear G that occurs on the floor 52 of the vehicle 12. Thus, for example, the floor G sensor 28 mounted on the vehicle 12 as a standard together with the driver seat airbag device 14 can also be used as a braking condition detection unit. Therefore, it contributes to simplification of the configuration and cost reduction.

  Next, a second embodiment of the present invention will be described. In addition, about the structure and effect | action fundamentally similar to 1st Embodiment, 1st Embodiment and a same sign are provided and the description is abbreviate | omitted.

Second Embodiment
FIG. 5 shows a vehicle air bag system 70 according to a second embodiment of the present invention in a side view corresponding to FIG. This embodiment is basically configured the same as the first embodiment, but differs in the following points. That is, in this embodiment, the steering column 31 includes a telescopic mechanism for adjusting the length of the steering column 31 in the longitudinal direction of the vehicle, and a tilt mechanism for adjusting the angle of the steering column 31 with respect to the vehicle 12. Is provided. Thereby, the position of the steering wheel 30 with respect to the vehicle 12 can be adjusted. Further, a steering sensor 72 as a steering position detection unit for detecting the adjusted position of the steering wheel 30 is attached to the steering column 31. The steering sensor 72 is electrically connected to the air bag ECU 22.

  In this embodiment, the air bag ECU 22 basically performs the same process as the flowchart shown in FIG. 4, but the following points are different from the first embodiment. That is, in this embodiment, the process of the airbag ECU 22 detecting the position of the steering wheel 30 with respect to the vehicle 12 based on the output signal of the steering sensor 72 is added. This process is performed before or after the process of step S1. The detection result is used when the air bag ECU 22 estimates the distance between the occupant P and the steering wheel 30 after forward movement in step S4.

  That is, in step S4, the airbag ECU 22 detects the position of the occupant P before the forward movement detected by the seat slide sensor 18, the position of the steering wheel 30 detected by the steering sensor 72, and the forward movement amount L calculated in step S3. And estimate the distance between the occupant P and the steering wheel 30 after forward movement. Thus, even if the steering wheel 30 is configured to be position adjustable, the accuracy of the distance estimated by the airbag ECU 22 can be ensured.

<Supplementary explanation of the embodiment>
In each of the above embodiments, the occupant P is seated on the driver's seat 13 and the airbag 32 is housed in the steering wheel 30, but the present invention is not limited to this. That is, the occupant in the front seat may be seated in the front passenger seat (front seat: not shown), and the air bag 32 may be accommodated in the instrument panel 15 positioned in front of the occupant in the front passenger seat.

  Moreover, although the case where this invention was applied with respect to the vehicle 12 provided with the automatic brake system was demonstrated in said each embodiment, it does not restrict to this. The present invention is particularly effective for a vehicle equipped with an automatic braking system, but is also applicable to a vehicle not equipped with an automatic braking system.

  In each of the above-described embodiments, when it is estimated that the distance between the occupant P and the steering wheel 30 is short in step S5, both the upper and lower actuators 40 and 42 are not activated in step S9. It is not limited to this. That is, while the upper actuator 40 is actuated in step S9, the lower actuator 42 may not be actuated. As a result, the lower side of the air bag 32 is limited in expansion in the longitudinal direction of the vehicle, so the lower side of the air bag 32 is smoothly inflated and deployed between the chest and the abdomen of the occupant P and the lower side of the steering wheel 30. be able to. Further, since the upper side of the air bag 32 is not limited to the expansion in the longitudinal direction of the vehicle, the occupant restraining performance on the upper side of the air bag 32 is improved.

  In each of the above embodiments, the steering wheel 30 is configured to be non-rotation center pad type, but the present invention is not limited thereto. The center pad portion 30A is configured to be integrally rotated with the grip portion 30B. It is also good. In this case, if the position of the lower portion of the air bag 32 can be detected by providing a rotational angle sensor for detecting the rotational angle of the steering wheel 30, the expansion limitation of only the lower side of the air bag 32 described above (upper and lower It becomes possible to apply control) which operates only the upper actuator 40 among the actuators 40 and 42.

  In each of the above embodiments, the expansion limiting portion 16 is configured to include the pair of straps 36 and 38 and the pair of actuators 40 and 42. However, the present invention is not limited thereto, and the number of straps and actuators is Can be changed as appropriate. For example, the longitudinal middle portions of one strap may be engaged with one actuator, and the longitudinal ends of the one strap may be fixed at mutually separated positions on the tip side of the air bag 32. Good.

  Further, in the first embodiment, the air bag ECU 22 detects the seat slide position detected by the seat slide sensor 18 on the vehicle front side of the position set in advance and the floor G sensor 28 detects it just before a frontal collision. If the inertial movement amount L calculated by time integration of the back and forth G is equal to or more than a preset amount, it is estimated that the distance between the occupant P after the forward movement and the steering wheel 30 is less than the reference value. Is configured to be inoperative, but is not limited thereto.

  For example, when the seat slide position detected by the seat slide sensor 18 is on the front side of the vehicle relative to a preset position, the airbag ECU 22 detects an occupant P and the steering wheel 30 at the time of a frontal collision (frontal collision detection). It is possible to estimate that the distance of d is less than the reference value, and to make the actuators 40 and 42 inoperable. In addition, for example, the airbag ECU 22 can steer the occupant P after the forward movement and the steering when the inertial movement amount L calculated by time integration of the longitudinal G detected by the floor G sensor 28 immediately before the frontal collision is equal to or more than a preset amount. The distance between the wheel 30 and the wheel 30 may be estimated to be less than the reference value, and the actuators 40 and 42 may be inactivated.

  In addition, the present invention can be implemented with various modifications without departing from the scope of the invention. Of course, the scope of rights of the present invention is not limited to the above embodiments.

10 Vehicle Airbag System 12 Vehicle 13 Driver's Seat 16 Expansion Restriction Unit 18 Seat Slide Sensor (Occupant Position Detection Unit)
20 control device 28 floor G sensor (acceleration sensor, braking condition detection unit)
Reference Signs List 30 steering wheel 32 air bag 36, 38 strap 52 floor 54 seat back angle sensor (occupant position detection unit)
56 Seatback Capacitance Sensor (Occupant Position Detector)
58 Seat cushion load sensor (Occupant position detector)
60, 62 Seat leg load sensor (Occupant position detection unit)
64 In-car camera (Occupant position detection unit)
66 Brake pressure sensor (braking condition detector)
70 Vehicle Airbag System 72 Steering Sensor (Steering Position Detector)
P crew

Claims (5)

An airbag which is accommodated in an interior part positioned in front of a front seat occupant of the vehicle and inflates and deploys between the front seat occupant and the interior part when the vehicle makes a frontal collision;
An expansion restricting portion capable of restricting expansion of the air bag in the vehicle longitudinal direction by a strap attached to the air bag, and capable of releasing the restriction.
An occupant position detection unit that detects the position of the front seat occupant with respect to the vehicle;
A braking status detection unit that detects the braking status of the vehicle;
Using the detection results of the occupant position detection unit and the braking condition detection unit, the distance between the front-seat occupant and the interior parts after inertial movement to the front side by braking of the vehicle just before a frontal collision is estimated A control device that cancels the restriction when the distance is equal to or greater than a reference value, and maintains the restriction when the distance is less than the reference value;
Vehicle airbag system equipped with The interior part is a steering wheel whose position relative to the vehicle is adjustable,
The vehicle further includes a steering position detection unit that detects the position of the steering wheel with respect to the vehicle.
The vehicle air bag system according to claim 1, wherein the control device uses a detection result of the steering position detection unit when estimating the distance. The occupant position detection unit is a seat slide sensor that detects the position of the front passenger with respect to the vehicle based on the seat slide position of the front seat on which the front passenger sits.
The braking condition detection unit is an acceleration sensor that detects the braking condition based on acceleration in a vehicle longitudinal direction generated on a floor of the vehicle.
The control device is configured such that the amount of the inertial movement calculated by time integration of the acceleration immediately before the frontal collision is greater than a predetermined amount on the vehicle front side of the position where the seat slide position is preset. The vehicle airbag system according to claim 1 or 2, wherein it is estimated that the distance is less than a reference value. The vehicle air bag system according to any one of claims 1 to 3, wherein the braking state detection unit is a floor G sensor that detects an acceleration in the front-rear direction that occurs on a vehicle floor near a central portion of the vehicle. The expansion limiting portion is
A pair of upper and lower straps disposed in the air bag, one end of which is fixed to the tip of the air bag;
And a pair of upper and lower actuators accommodated in the air bag on the base end side of the air bag, the other ends of the pair of upper and lower straps being engaged and operated to be released by the engagement. Yes,
The controller is
If the distance is equal to or greater than a reference value, operate the pair of upper and lower actuators;
The vehicle airbag system according to any one of claims 1 to 4, wherein when the distance is less than a reference value, the upper actuator is actuated while the lower actuator is not actuated.

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