JP2005193832A - Air bag device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air bag device for a vehicle capable of automatically transferring an air bag unit from a first position to a second position approaching to an occupant by predicting collision of the vehicle and reducing deployment force of the air bag rearwardly deployed at collision of the vehicle. <P>SOLUTION: The air bag device for the vehicle is constituted such that an air bag movement mechanism 21 for moving the air bag unit 20 with a steering wheel 2 from the first position to the second position approaching to the occupant than the first position is provided, when the collision of the vehicle is predicted, the air bag unit 20 is automatically moved from the first position to the second position, and at the collision of the vehicle, the air bag 31 is rearwardly deployed from the steering wheel 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a vehicle airbag device that protects an occupant during a vehicle collision.

  2. Description of the Related Art Conventionally, an airbag device for a driver's seat mounted on a vehicle such as an automobile is equipped with an airbag unit having an airbag and an inflator on a steering wheel, and a control device is electrically connected to the inflator. . A collision sensor is connected to the control device. When a collision of the vehicle is detected by the collision sensor, the control device energizes the inflator to generate gas, and the airbag is deployed rearward by the gas pressure.

  The air bag unit is provided integrally with the steering wheel. Usually, the distance between the steering wheel and the occupant (driver) is relatively large, and in the event of a vehicle collision, the air bag is quickly moved backward between the steering wheel and the occupant. And it is necessary to develop it greatly. On the other hand, Patent Document 1 discloses a technology for controlling the deployment of an airbag by adjusting the gas flow flowing into and out of the airbag according to the vehicle speed, the seat position, size, weight, and the like of the occupant.

Patent Document 2 discloses a steering device that controls a turning angle of a wheel based on a steering angle of a steering wheel mechanically separated from a steerable wheel.
Japanese translation of PCT publication No. 2002-501459 JP 2000-344117 A

  In a conventional airbag device for a driver's seat, as described above, the airbag unit is provided integrally with the steering wheel, and the position of the airbag unit is fixed. Usually, the steering wheel (airbag unit) and the occupant are fixed. Since the distance between them is relatively large, it is necessary to quickly and largely deploy the airbag rearward between the steering wheel and the occupant at the time of a vehicle collision, which increases the deployment force of the airbag. Therefore, there is a limit to downsizing the inflator.

  Although the technology that can adjust the position of the steering wheel back and forth is known, assuming that the distance between the steering wheel and the occupant becomes relatively large depending on the position of the steering wheel, the airbag can be quickly moved backward in the event of a vehicle collision. In addition, it is necessary to deploy a large amount, the same problem as described above occurs, and if the distance between the steering wheel and the occupant becomes small, the deployment force of the airbag may be too large.

  On the other hand, in the airbag device disclosed in Patent Document 1, the airbag is deployed and controlled by adjusting the gas flow flowing into and out of the airbag according to the vehicle speed, the seat position of the occupant, and the like. In the case of a vehicle collision in which the distance between the passengers is relatively large and particularly the impact force is large, it is necessary to quickly and largely deploy the airbag rearward between the steering wheel and the occupant, which causes the same problem as described above. .

  An object of the present invention is to predict the collision of a vehicle and automatically move an airbag unit from a predetermined first position to a second position approaching an occupant in a vehicular airbag device, and to deploy rearward in the event of a vehicle collision. Reducing the deployment force of the airbag, absorbing the impact force acting on the airbag unit and the steering wheel reliably, deploying the airbag to an appropriate size, and moving the airbag unit to the second position. For example, prohibiting the movement as appropriate, and automatically returning the airbag unit under appropriate conditions when the vehicle collision prediction is an erroneous prediction.

  According to a first aspect of the present invention, there is provided a vehicle airbag device including a steering device that controls a turning angle of a steerable wheel based on a steering angle signal of the steering wheel. An airbag unit having an airbag that can be deployed rearward; a collision detection unit that detects a collision of the vehicle; and an airbag deployment unit that deploys the airbag when the collision detection unit detects a collision of the vehicle; An airbag moving means for moving the airbag unit between a predetermined first position and a second position closer to the occupant than the first position; a collision prediction means for predicting a collision of the vehicle; and the collision Controls the airbag moving means to move the airbag unit from the first position to the second position when the prediction means predicts a vehicle collision. That it is characterized in that it comprises an air bag movement control means.

  For example, the airbag moving means is configured to have an actuator such as a hydraulic cylinder or an electric motor, and is disposed in front of the steering wheel. The actuator is driven and controlled by the airbag movement control means, and the airbag is moved. The unit moves between the first position and the second position. For example, the airbag unit is provided integrally with the steering wheel, and the steering shaft is driven in the length direction by the airbag moving means, so that the airbag unit is moved between the first position and the second position together with the steering wheel. Move. Alternatively, the airbag unit is detachable from the steering wheel, and only the airbag unit moves between the first position and the second position.

  In this airbag device, the steering angle of the steerable wheel is controlled in the steering device based on the steering angle signal of the steering wheel. When the vehicle collides, first, when a collision of the vehicle is predicted by the collision prediction means, the airbag movement control means is controlled by the airbag movement control means, and the airbag unit is moved from the first position by the airbag movement means. When the vehicle is moved to the second position and then a collision of the vehicle is detected by the collision detection means, the airbag is deployed rearward by the airbag deployment means. At this time, if the airbag unit is located at the second position closer to the occupant than the first position, the distance between the airbag unit and the occupant is reduced, so the airbag is compared rearward by the airbag deployment means. It is configured to expand to a small size.

  According to a second aspect of the present invention, in the first aspect of the invention, the vehicle airbag apparatus moves the airbag unit from the second position to the first position by the impact force received from the occupant acting on the airbag moving means when the vehicle collides. This is characterized in that an impact absorbing means for absorbing is provided. When the vehicle collides, the impact force received from the occupant by the airbag unit or a member (steering wheel) provided integrally with the airbag unit acts on the airbag moving means, and the airbag unit is moved from the second position to the first position. It is absorbed reliably by moving to.

  According to a third aspect of the present invention, there is provided a vehicular airbag apparatus according to the first aspect of the present invention, wherein the airbag deployment means deploys either the first deployed state or the second deployed state in which the airbag is deployed with a smaller deployment force than the first deployed state. The airbag deployment means is configured to deploy the airbag in the first deployed state when the airbag unit is located at the first position when the vehicle collides, and the vehicle collision Sometimes, when the airbag unit is located at the second position, the airbag is deployed to the second deployed state.

  When the airbag unit is located at the first position at the time of the vehicle collision, the airbag is deployed to the first deployed state by the airbag deployment means, and the airbag unit is closer to the occupant than the first position at the time of the vehicle collision. When it is located at the second position, the distance between the airbag unit and the occupant is reduced, and the airbag is deployed to the second deployed state by the airbag deployment means with a smaller deployment force than the first deployed state.

  According to a fourth aspect of the present invention, when the impact force received by the occupant at the time of the vehicle collision is smaller than a predetermined value, the airbag unit is located at the first position at the time of the vehicle collision. Even in this case, the airbag deploying means deploys the airbag in the second deployed state. When the impact force received by the vehicle occupant is small, the airbag is deployed to the second deployed state by the airbag deployment means regardless of the position of the airbag unit.

  According to a fifth aspect of the present invention, there is provided a vehicular airbag apparatus according to the first aspect of the present invention, further comprising an impact force estimating means for estimating an impact force received by an occupant at the time of a vehicle collision. When the value is smaller than the value, the airbag movement control means prohibits the movement of the airbag unit to the second position. The impact force at the time of vehicle collision is estimated by the impact force estimation means, and when the impact force is smaller than a predetermined value, the airbag unit is held at the first position, and from the airbag unit at the first position at the time of the vehicle collision. The airbag deploys backward.

  According to a sixth aspect of the present invention, there is provided the vehicle airbag device according to the first aspect, wherein when the collision prediction means predicts a collision of the vehicle, the airbag movement control means when a steering angle of a steering wheel is a predetermined value or more. Is characterized by prohibiting the movement of the airbag unit to the second position. When a collision of the vehicle is predicted by the collision prediction means during the avoidance steering of the steering wheel for avoiding the collision of the vehicle, the movement of the airbag unit to the second position is performed so as not to hinder the avoidance steering. The airbag unit is held in the first position.

  According to a seventh aspect of the present invention, there is provided a vehicle airbag apparatus according to the first aspect of the present invention, further comprising: an erroneous prediction detection means capable of detecting whether a vehicle collision predicted by the collision prediction means has actually occurred, and the erroneous prediction detection means. When it is detected that a vehicle collision has not actually occurred, the airbag movement control means sets the airbag unit positioned at the second position when the predetermined return condition is satisfied. It is characterized by returning to one position. When the erroneous prediction detection means detects that a vehicle collision did not actually occur (collision erroneous prediction), and then the predetermined return condition is satisfied, the airbag unit automatically moves to the first position. Return.

  According to an eighth aspect of the present invention, in the vehicle airbag device of the seventh aspect, the predetermined return condition includes a condition that a steering angle of a steering wheel is smaller than a predetermined value. When a misprediction of a vehicle collision is detected, the airbag unit is returned to the first position when the steering angle of the steering wheel is smaller than a predetermined value. During steering of the steering wheel, the airbag unit is moved to the first position. It can be configured not to return to.

  According to a ninth aspect of the present invention, in the vehicle airbag device of the eighth aspect, the predetermined return condition includes a condition that the vehicle speed is smaller than a predetermined value. When an erroneous vehicle prediction is detected, the airbag unit is returned to the first position when the vehicle speed is lower than the predetermined value, and the airbag unit is not returned to the first position when the vehicle is traveling at high speed. Can be configured.

  According to a tenth aspect of the present invention, in the first aspect of the invention, when the collision predicting means predicts a collision of the vehicle, the steering angle of the wheel is maintained after the airbag unit starts moving. It is characterized by comprising. After the airbag unit starts to move, the wheel turning angle is prevented from being changed by steering the steering wheel.

  According to an eleventh aspect of the present invention, there is provided a vehicle airbag apparatus according to any one of the first to tenth aspects, wherein the steering wheel is integrally provided with an airbag unit, and the airbag moving means includes the airbag unit together with the steering wheel. It is characterized by being moved over the position and the second position. By moving the steering wheel by the airbag moving means, the airbag unit can be moved between the first position and the second position, and the occupant can be stably received over a wide area of the entire steering wheel. it can.

  According to the vehicle airbag device of the first aspect, the airbag unit, the collision detection unit, the airbag deployment unit, the airbag moving unit, the collision prediction unit, and the airbag movement control unit provided on the steering wheel are provided. When the vehicle collides, first, the vehicle collision is predicted and the airbag unit is automatically moved from the first position to the second position approaching the occupant, and then the vehicle collision is detected to detect the airbag. Can be deployed backwards. At this time, if the airbag unit is located at the second position, the distance between the airbag unit and the occupant is small, so that the airbag can be deployed relatively small rearward. That is, the deployment force of the airbag can be reduced, and the airbag can be deployed small and quickly, and the occupant can be received by the airbag. As a result, the inflator that generates gas for deploying the airbag can be downsized.

  According to the vehicle airbag device of the second aspect, the impact absorption that absorbs the impact force received from the occupant acting on the airbag moving means at the time of the vehicle collision by moving the airbag unit from the second position to the first position. Since the means is provided, the impact force from the occupant received by the airbag unit or a member (steering wheel) provided integrally with the airbag unit at the time of a vehicle collision acts on the airbag moving means. Since the airbag unit is moved from the second position toward the first position (forward) while absorbing the impact from the occupant, the impact received by the occupant can be reduced.

  According to the vehicle airbag device of the third aspect, when the airbag unit is located at the first position at the time of the vehicle collision, the airbag is deployed to the first deployed state by the airbag deployment means, and the airbag is When the bag unit is located at the second position closer to the occupant than the first position, the distance between the airbag unit and the occupant is reduced, so that the airbag is smaller than the first deployed state by the airbag deployment means. The occupant can be received by the airbag deployed in the second deployed state with the deployed force and deployed with a small deployed force in the second position. As described above, the airbag can be deployed with an appropriately sized deployment force in accordance with the position of the airbag unit.

  According to the vehicle airbag device of claim 4, when the impact force received by the occupant at the time of the vehicle collision is small, even when the airbag unit is located at the first position at the time of the vehicle collision, Since the airbag is deployed in the second deployed state, regardless of the position of the airbag unit, the airbag is deployed in the second deployed state by the airbag deployment means, and the occupant is received by the airbag deployed with a small deployment force. Can do.

  According to the vehicle airbag device of the fifth aspect, since the impact force estimation means for estimating the impact force received by the occupant at the time of the vehicle collision is provided, the impact force at the time of the vehicle collision can be reliably estimated, and the impact force is When the air bag unit is smaller than the predetermined value, the air bag movement control means prohibits the movement of the air bag unit to the second position. Therefore, when the estimated impact force is small, the air bag unit is unnecessarily moved to the second position. The operability of the collision avoidance operation by steering the steering wheel can be ensured without being moved to.

  According to the vehicle airbag device of the sixth aspect, when the collision predicting means predicts the collision of the vehicle, the airbag movement control means is configured such that when the steering angle of the steering wheel is not less than a predetermined value, the airbag movement control means Since the movement to the second position is prohibited, when the collision prediction means predicts the collision of the vehicle during the steering wheel avoidance steering for avoiding the collision of the vehicle, the movement of the airbag unit to the second position is prohibited. By prohibiting and holding the airbag unit in the first position, it is possible to prevent the steering wheel from being obstructed.

  According to the vehicle airbag device of the seventh aspect, the erroneous prediction detection means capable of detecting whether the collision of the vehicle predicted by the collision prediction means has actually occurred is provided, and the erroneous prediction detection means actually detects the collision of the vehicle. When it is detected that no occurrence has occurred (collision error prediction), the airbag movement control means moves the airbag unit located at the second position to the first position when a predetermined return condition is satisfied. Since the return movement is performed, the safety of the driving can be maintained without causing the support to the driving by automatically returning the airbag unit to the first position after detecting the erroneous prediction of the collision of the vehicle.

  According to the vehicle airbag device of the eighth aspect, since the predetermined return condition includes a condition that a steering angle of the steering wheel is smaller than a predetermined value, the steering wheel is detected when an erroneous collision prediction of the vehicle is detected. When the steering angle is smaller than a predetermined value, the airbag unit can be returned to the first position, and the airbag unit can be prevented from returning to the first position while the steering wheel is being steered. It can be avoided.

  According to the vehicle airbag device of the ninth aspect, since the predetermined return condition includes a condition that the vehicle speed is smaller than a predetermined value, the vehicle speed is lower than the predetermined value when a vehicle collision erroneous prediction is detected. When the vehicle is small, the airbag unit can be returned to the first position, and when the vehicle is traveling at high speed, the airbag unit can be prevented from returning to the first position. Therefore, safety can be ensured.

  According to the vehicle airbag device of the tenth aspect, when the collision predicting means predicts the collision of the vehicle, the steering angle of the wheel disconnected from the steering wheel is maintained after the airbag unit starts moving. Since it comprised as mentioned above, it can prevent making a vehicle into an unstable state by the change of the steering angle of the wheel immediately before a collision.

  According to the vehicle airbag device of the eleventh aspect, the airbag unit is integrally provided on the steering wheel, and the airbag moving means moves the airbag unit over the first position and the second position together with the steering wheel. Therefore, by moving the steering wheel by the airbag moving means, the airbag unit can be moved over the first position and the second position, and the occupant can be stably stabilized over a wide area of the entire steering wheel. I can take it.

  A vehicle airbag apparatus according to the present invention includes a steering apparatus that controls a steering angle of a wheel based on a steering angle signal of a steering wheel that is mechanically disconnected from a steerable wheel. (Vehicle), an airbag unit provided on a steering wheel and having an airbag that can be deployed rearward at the time of a vehicle collision, a collision detection unit that detects a vehicle collision, and a collision detection unit that detects a vehicle collision An airbag deployment means for deploying the airbag; an airbag moving means for moving the airbag unit between a predetermined first position and a second position closer to the occupant than the first position; When the collision prediction means for predicting and the collision prediction means foreseeing a collision of the vehicle, the air bag unit is moved from the first position to the second position. It is obtained and an air bag movement control means for controlling the grayed moving means.

  As shown in FIGS. 1 and 2, the vehicle 1 controls the turning angle of the front wheel 3 based on a steering angle signal of the steering wheel 2 that is mechanically disconnected from the steerable front wheel 3. A steering device 4 that performs this operation and an airbag device 5 that deploys the airbag 31 of the airbag unit 20 provided on the steering wheel 2 rearward when the vehicle collides are mounted.

  The steering device 4 includes an STG steering angle sensor 10 (steering steering angle sensor 10) for detecting the steering angle of the steering wheel 2 and a pair of wheel steering actuators 11 (for example, changing the steering angle of the pair of front wheels 3). , An electric motor), and an ECU 6 (electronic control unit 6) to which the STG steering angle sensor 10 and a pair of wheel turning actuators 11 are electrically connected. The ECU 6 controls driving of the wheel turning actuator 11 based on the sensor signal from the STG steering angle sensor 10 and controls the turning angle of the front wheel 3.

  The airbag device 5 includes an airbag unit 20 provided integrally with the steering wheel 2, and the steering wheel 2 together with the airbag unit 20 at a predetermined first position (see, for example, FIGS. 3-1 and 3-2). And an air bag moving mechanism 21 having a hydraulic cylinder 22 and a hydraulic pressure supply device 23 that are moved over a second position closer to the occupant (driver) than the first position (see, for example, FIG. 3C). ECU 6, STG steering angle sensor 10, vehicle speed sensor 24, collision sensor 25, distance sensor 26, STG position sensor 27 (steering position sensor 27), occupant weight sensor 28, etc. electrically connected to ECU 6. Yes.

  An airbag control program is stored in the control unit of the ECU 6, and the ECU 6 performs the STG steering angle sensor 10, the vehicle speed sensor 24, the collision sensor 25, the distance sensor 26, and the STG position sensor 27 based on the airbag control program. In response to various sensor signals from the occupant weight sensor 28, the inflator 32 and the tether fixing / releasing mechanism 33 of the airbag unit 20 and the switching valve 48 of the hydraulic pressure supply device 23 are driven and controlled based on the sensor signals. Air bag control, which will be described later in detail, is realized.

  The collision sensor 25 corresponds to a collision detection unit that detects a vehicle collision. The distance sensor 26 includes an ultrasonic sensor or an infrared sensor that can measure the relative distance between the automobile 1 and a relative object (for example, another automobile or a fixed object in front of the automobile 1). In response to the sensor signal from the sensor 26, the relative distance and relative speed with respect to the relative object are calculated, and the relative object and the predetermined time (for example, for example, based on the relative distance and relative speed and a preset collision prediction map) Predict that a collision will occur after 1 second). That is, the distance sensor 26 and the ECU 6 correspond to a collision prediction means for predicting a vehicle collision.

  Further, the distance sensor 26 and the ECU 6 correspond to impact estimation means for estimating impact force at the time of vehicle collision. In the case of the present embodiment, the ECU 6 receives the sensor signal from the distance sensor 26, calculates the relative speed with the relative object, and estimates the impact force with the relative speed. Further, the ECU 6 corresponds to erroneous prediction detection means that can detect whether a collision predicted by the collision prediction means actually occurred (that is, erroneous prediction). In this case, the ECU 6 determines that the collision prediction of the vehicle is an erroneous prediction when no collision is detected even after a predetermined time T (for example, T = 1 second) has elapsed after the collision prediction.

  The STG position sensor 27 includes, for example, a proximity switch provided in the hydraulic cylinder 22 of the airbag moving mechanism 21, and detects the position of the piston 22b, thereby detecting the position of the steering wheel 2 (airbag unit 20). Further, the occupant weight sensor 28 is provided inside the seat cushion 1b of the driver's seat and detects the weight of the occupant seated on the seat cushion 1b.

  As shown in FIG. 4, the airbag unit 20 is fixed to the inside of the steering wheel 2 and has a casing 30 in which the rear wall of the occupant forms a fragile portion. An inflatable airbag 31, an inflator 32 that is energized by the ECU 6 in the event of a vehicle collision, generates gas, breaks the fragile portion backward by the gas pressure, and a tether fixing / releasing mechanism 33 are provided. .

  The tether fixing / releasing mechanism 33 has a restraining member 33a that can be fixed / released with respect to the airbag 31, and the tether fixing / releasing mechanism 33 is controlled by the ECU 6 at the time of a vehicle collision so that the restraining member 33a is removed from the airbag 31. When separated from the airbag 31, as shown in FIG. 3-1, the airbag 31 is largely deployed rearward in the first deployed state, and the restraining member 33a is not separated from the airbag 31, as shown in FIGS. As shown in FIG. 3, the airbag 31 is deployed to the second deployed state with a deployment force smaller than that of the first deployed state. The tether fixing / releasing mechanism 33 is for breaking the attachment portion of the restraining member 33a by a signal from the ECU 6, for example.

  Here, the ECU 6 and the inflator 32 correspond to deployment means for deploying the airbag 31 when the collision sensor 25 detects a collision of the vehicle. The deployment means further includes a tether fixing / releasing mechanism 33, and its deployment. By the means, the airbag 31 is configured to be deployed alternatively to either the first deployed state or the second deployed state in which the airbag 31 is deployed with a smaller deployment force than the first deployed state.

  As shown in FIGS. 5-1 to 5-3, the airbag moving mechanism 21 includes a return hydraulic cylinder 22 disposed on the front side of the steering wheel 2, and a hydraulic pressure supply that supplies hydraulic pressure to the hydraulic cylinder 22. Device 23. The steering shaft 2a is connected to the piston rod 22a of the hydraulic cylinder 22, and an orifice 40 is formed in the piston 22b to connect the base end side oil chamber and the tip end side oil chamber on both sides thereof. Is provided.

  The hydraulic pressure supply device 23 includes oil passages 45 a to 45 d, a reserve tank 46, a hydraulic pump 47, and a switching valve 48, and the switching valve 48 is driven and controlled by the ECU 6. Normally, as shown in FIG. 5A, the switching valve 48 is switched, the oil passages 45c and 45d are separated, and the steering wheel 2 and the airbag unit 20 are held in the first position. For example, the hydraulic pump 47 is a pump that always operates when the engine is operated. As shown in FIG. 5A, when the switching valve 48 is switched, the oil passages 45a and 45b are connected, and the oil discharged from the hydraulic pump 47 is It is returned to the reserve tank 46.

  As shown in FIG. 5B, when the switching valve 48 is switched, the oil passages 45a and 45c are connected, and the oil passages 45b and 45d are connected, the hydraulic pump 47 causes the base end side oil chamber to enter the oil chamber. Hydraulic pressure is supplied, and the steering wheel 2 and the airbag unit 20 move from the first position toward the second position. Also, as shown in FIG. 5C, when the switching valve 48 is switched, the oil passages 45a and 45d are connected, and the oil passages 45b and 45c are connected, the hydraulic pump 47 causes the oil chamber at the front end side of the hydraulic cylinder 22 to be connected. The hydraulic pressure is supplied to the steering wheel 2 and the airbag unit 20 moves from the second position toward the first position.

  By the way, as shown in FIGS. 5-1 to 5-3, the impact force received from the occupant acting on the airbag moving mechanism 21 from the steering wheel 2 at the time of the vehicle collision is first detected from the second position. An impact absorbing mechanism 49 is provided for absorbing by moving to a position. In the case of the present embodiment, the shock absorbing mechanism 49 has an orifice 40 formed in the piston 22b, and when the steering wheel 2 is located at the second position, the base end of the hydraulic cylinder 22 due to the impact force received by the piston 22b. The oil in the side oil chamber gradually flows through the orifice 40 to the tip side oil chamber, whereby the steering wheel 2 gradually moves toward the first position together with the piston 22b, and the impact force is absorbed.

  Next, the airbag control executed by the ECU 6 based on the airbag control program is shown in the flowcharts of FIGS. 6 to 8 (Si (i = 1, 2, 3,... In the figure indicates each step)). This will be explained based on. The direction in which the steering wheel 2 approaches the passenger will be described as a first direction, and the direction in which the steering wheel 2 is separated from the passenger will be described as a second direction.

  As shown in FIG. 6, this airbag control is started when the ignition switch is turned on. First, the STG steering angle sensor 10, the vehicle speed sensor 24, the collision sensor 25, the distance sensor 26, the STG position sensor 27, the occupant weight. Various sensor signals are read from the sensor 28 (S1), and a collision prediction determination process (S2) is executed using the sensor signals from the distance sensor 26. As a result of the collision prediction determination process, if it is predicted that a vehicle collision will occur after a predetermined time (S3; Yes), the process proceeds to S4. If not (S3; No), the process proceeds to S12.

  In the impact force estimation process of S4, the impact force when colliding with a relative object is estimated by the relative speed with the relative object using the sensor signal from the distance sensor 26, and then the relative speed is preliminarily determined. When it is determined that the impact force is equal to or greater than the predetermined value (for example, 40 km / h) (impact force: large) (S5; No), the process proceeds to S6, and the relative speed is greater than the predetermined value. If it is determined that the impact force is smaller than the predetermined value (impact force: small) (S5; Yes), the process proceeds to S12.

  Next, in S6, the STG steering angle obtained from the sensor signal from the STG steering angle sensor 10 is a predetermined value (for example, ± 45 degrees, for example, the turning angle of the front wheels 3 at this time ± 5 degrees) or more. (S6; Yes), the process proceeds to S7, and when the STG steering angle is smaller than the predetermined value (S6; No), the process proceeds to S8. In S7, after the steering wheel 2 starts moving in the second direction, it is determined whether or not the STG steering angle is equal to or greater than a predetermined value. In this case (S7; Yes), that is, after the vehicle collision is predicted, the STG steering angle is If it is equal to or greater than the predetermined value, the process proceeds to S8. If not (S7; No), that is, if the STG steering angle is equal to or greater than the predetermined value before the vehicle collision prediction, the process proceeds to S12. .

  Thus, when a vehicle collision is predicted (S3; Yes) and the estimated impact force is large (S5; No), when the STG steering angle is smaller than a predetermined value (S6; No), or STG Even when the steering angle is larger than the predetermined value (S6; Yes), when the STG steering angle becomes equal to or larger than the predetermined value after the steering wheel 2 starts moving in the second direction (S7; Yes), Steering of the steering wheel 2 becomes invalid, and the turning angle of the front wheel 3 is maintained (S8).

  Next, it is determined whether or not the movement amount (position) of the steering wheel 2 in the second direction obtained by the STG position sensor 27 is the maximum value (maximum movement position) (S9). When the amount of movement of the steering wheel 2 in the second direction is smaller than the maximum value (S9; Yes), the switching valve 48 is switched as shown in FIG. 5-2, and the steering wheel 2 is moved in the second direction. Move (S10). Since the steering wheel 2 is normally located at the first position, the process first proceeds from S9 to S10, and the steering wheel 2 moves in the second direction.

  When the amount of movement of the steering wheel 2 in the second direction reaches the maximum value (S9; No), the switching valve 48 is switched as shown in FIG. 5-1, and the movement of the steering wheel 2 is stopped. The position is locked (S11). Here, based on the weight of the occupant obtained by the occupant weight sensor 28, the maximum value in S9 may be set, and the moving speed of the steering wheel 2 in the second direction in S10 may be set.

  Next, as shown in FIG. 7, when a vehicle collision is detected based on the sensor signal from the collision sensor 25 (S12; Yes), when the steering wheel 2 is moving in the second direction, As shown in FIG. 5A, the switching valve 48 is switched, the movement of the steering wheel 2 is stopped and its position is locked (S13), and then the amount of movement of the steering wheel 2 in the second direction is predetermined. It is determined whether or not the value is larger (S14).

  When the amount of movement of the steering wheel 2 in the second direction is larger than a predetermined value (S14; Yes), that is, when the steering wheel 2 is located at the second position as shown in FIG. Gas is generated by energizing the inflator 32, and the restraining member 33a is not separated from the airbag 31 by the tether fixing / releasing mechanism 33, and the airbag 31 is deployed backward in the second deployed state (small size) (S16). .

  Further, when the movement amount of the steering wheel 2 in the second direction is equal to or smaller than the predetermined value (S14; No), that is, the steering wheel 2 is positioned at the first position as shown in FIGS. If the impact force at the time of vehicle collision is smaller than a predetermined value (S15; Yes), that is, the relative speed with the relative object (collision object) at the time of the vehicle collision is a predetermined value (for example, 30 km) If it is smaller than / h), the airbag 31 is deployed rearward in the second deployed state (small size) as shown in FIG. 3-2 (S16).

  In addition, when the impact force at the time of the vehicle collision is greater than or equal to a predetermined value (S15; No), that is, when the relative speed with the relative object (the collision object) at the time of the vehicle collision is greater than or equal to the predetermined value, the inflator 32 is energized. Gas is generated, and the restraining member 33a is separated from the airbag 31 by the tether fixing / releasing mechanism 33, and the airbag 31 is deployed rearward in the first deployed state (large size) as shown in FIG. ).

  On the other hand, if no vehicle collision is detected in S12 (S12; No), it is determined whether or not a predetermined time T (for example, T = 1 second) has elapsed since the steering wheel 2 started to move in the second direction ( S19) When the predetermined time T has elapsed (S19; Yes), an erroneous prediction process (S20) is executed and the process returns. When the predetermined time T has not elapsed (S19; No), the process returns.

  In the erroneous prediction process of S20, as shown in FIG. 8, when the STG steering angle is smaller than a predetermined value (for example, ± 30 degrees) (S21; Yes), it is sounded that the steering wheel 2 is returned to the original position. As shown in FIG. 5-3, the changeover valve 48 is switched and the steering wheel 2 moves in the first direction to return to the original first position (S23). Even when the STG steering angle is greater than or equal to a predetermined value (S21; Yes), if the vehicle speed obtained from the sensor signal from the vehicle speed sensor 24 is smaller than a predetermined value (for example, 25 km / h) (S24; Yes). The return notification is made (S22), and the steering wheel 2 moves in the first direction to return to the original first position (S23). However, if the vehicle speed is equal to or higher than the predetermined value (S24; No), the process returns.

  By performing this air bag control, first, in the event of a vehicle collision, as shown in FIG. 9, when the impact force is large and the avoidance steering is none (the STG steering angle is approximately 0 degrees), the STG moves after the collision is predicted. As shown by the amount, when the steering wheel 2 moves in the second direction and moves to the maximum value that is the second position larger than the predetermined value until the collision is detected, the position is maintained at the position of the maximum value. When a collision is detected, the airbag 31 is deployed in a small size from the steering wheel 2 located at the second position.

  As shown in FIG. 10, when the impact force is large and the avoidance steering is none (the STG steering angle is approximately 0 degrees), the steering wheel 2 moves in the second direction after the collision is predicted, and the predetermined time until the collision is detected. If the movement does not exceed the first position below the value, the airbag 31 is deployed in size: large from the steering wheel 2 located at the first position when a collision is detected.

  As shown in FIG. 11, when the impact force is large, the avoidance steering is present (the STG steering angle is a predetermined value or more), and the STG steering angle is the predetermined value or more before the collision prediction, Even after the prediction, the turning angle of the front wheel 3 is controlled based on the steering angle of the steering wheel 2, and the movement of the steering wheel 2 in the second direction is prohibited after the prediction of the collision. The airbag 31 is deployed in a large size from the steering wheel 2 held at one position.

  As shown in FIG. 12, when the impact force is large, the avoidance steering is present (the STG steering angle is a predetermined value or more), and the steering wheel 2 is steered after the collision is predicted, the steering angle of the steering wheel 2 is Control of the turning angle of the front wheel 3 based on the above is prohibited, the turning angle of the front wheel 3 is held at the turning angle at the time of collision prediction, and when the steering wheel 2 is positioned at the first position when a collision is detected, When the airbag 31 is deployed at a size: large and the steering wheel 2 is positioned at the second position, the airbag 31 is deployed at a size: small.

  As shown in FIG. 13, when the impact force is small, the control of the turning angle of the front wheel 3 based on the steering angle of the steering wheel 2 is executed, but the second position of the steering wheel 2 even after the collision is predicted. When the collision is detected, the airbag 31 is deployed with the size: small from the steering wheel 2 held at the first position.

  As shown in FIG. 14, when the vehicle collision prediction is an erroneous prediction and the steering angle is small (the STG steering angle is approximately 0 degrees), the steering wheel 2 moves in the first direction after a predetermined time T has elapsed. In the case where the vehicle is predicted to return to the first position, and as shown in FIG. 15, when the vehicle collision prediction is an erroneous prediction, the steering angle is large (the STG steering angle is a predetermined value or more), and the vehicle speed is high → low. When the vehicle speed becomes equal to or lower than the predetermined value after the predetermined time T has elapsed, even when the STG steering angle is equal to or higher than the predetermined value, the steering wheel 2 moves in the first direction and returns to the first position.

According to the airbag apparatus 5 demonstrated above, there exist the following effects.
When a vehicle collides, first, the vehicle collision is predicted, the impact force at the time of the vehicle collision is estimated, and when the impact force is greater than or equal to a predetermined value, and when the STG steering angle is smaller than the predetermined value, The steering wheel 2 and the airbag unit 20 are automatically moved from the first position to the second position approaching the occupant, and then the collision of the vehicle is detected and the airbag 31 of the airbag unit 20 is deployed rearward. Can be made.

  At this time, since the airbag unit 20 is located at the second position and the distance between the airbag unit 20 and the occupant is small, the airbag 31 can be deployed rearward relatively small in the second deployed state. That is, the deployment force of the airbag 31 can be reduced, and the airbag 31 can be deployed small and quickly, and the occupant can be received by the airbag 31. As a result, the inflator 32 that generates gas for deploying the airbag 31 can be downsized.

  Since the impact absorbing mechanism 49 that absorbs the impact force acting on the airbag moving mechanism 21 at the time of a vehicle collision by moving the airbag unit 20 from the second position to the first position is provided, the steering wheel 2 at the time of the vehicle collision is provided. The impact force that the (airbag unit 20) receives from the occupant acts on the airbag moving mechanism 21, and the airbag moving mechanism 21 moves the airbag unit 20 from the second position to the first position while absorbing the impact from the occupant. Since the vehicle is moved in the forward direction, the impact received by the occupant can be reduced.

  When the airbag unit 20 is located at the first position at the time of the vehicle collision, the airbag 31 is deployed to the first deployed state, and when the airbag unit 20 is located at the second position at the time of the vehicle collision, Since the distance between the unit 20 and the occupant is reduced, the airbag 31 can be deployed in a second deployed state that is smaller than the first deployed state, and the occupant can be received by the airbag 31, and the impact during a vehicle collision can be achieved. When the force is small, the airbag 31 is deployed in the second deployed state even when the airbag unit 20 is located at the first position at the time of a vehicle collision. Therefore, regardless of the position of the airbag unit 20, the airbag 31. Can be expanded to the second expanded state. Thus, the airbag 31 can be deployed to an appropriate size according to the position of the airbag unit 20 and the magnitude of the impact force.

  The impact force at the time of the vehicle collision can be reliably estimated, and when the impact force is smaller than a predetermined value, the movement of the airbag unit 20 to the second position is prohibited, so the estimated impact force is small. In this case, the operability of the collision avoidance operation by steering the steering wheel 2 can be ensured without unnecessarily moving the airbag unit 20 to the second position.

  When a vehicle collision is predicted, if the steering angle of the steering wheel 2 is greater than or equal to a predetermined value, the airbag unit 20 is prohibited from moving to the second position. If a vehicle collision is predicted during avoidance steering, the airbag unit 20 is prohibited from moving to the second position and the airbag unit 20 is held at the first position so as not to hinder the avoidance steering. be able to.

  It is detected whether or not the vehicle collision prediction is a false prediction, and in the case of a false prediction, if a predetermined return condition is satisfied, the airbag unit 20 located at the second position is moved back to the first position. Therefore, after detecting the erroneous prediction of the collision of the vehicle, the airbag unit can be automatically returned to the first position while ensuring safety without driving support.

  The predetermined return condition includes a condition that the steering angle of the steering wheel 2 is smaller than a predetermined value, and further a condition that the vehicle speed is smaller than a predetermined value. Therefore, when a vehicle misprediction is detected, the steering wheel When the steering angle of 2 is smaller than a predetermined value, or when the vehicle speed is smaller than a predetermined value, the airbag unit 20 can be returned to the first position. Can be configured not to return the airbag unit 2 to the first position.

  When a vehicle collision is predicted, the steering angle of the front wheel 3 disconnected from the steering wheel 2 is maintained after the airbag unit 20 starts to move in the second direction. It is possible to prevent the vehicle from becoming unstable due to a sudden change in the turning angle of the wheels.

Next, a modified embodiment in which the above embodiment is partially modified will be described.
1] As an impact absorbing mechanism for absorbing an impact force acting on the airbag moving mechanism 21 at the time of a vehicle collision, a damper accumulator 50 is added to the impact absorbing mechanism 49 by connecting it to an oil passage 45c as shown in FIG. The shock absorbing mechanism 49A may be used. In this case, the switching valve 48 is switched at a high speed over the state shown in FIGS. 5-1 and 5-3, and further in the state shown in FIG. 5-2, and damping is performed. It is preferable to control the switching valve 48 so as to move gradually in the first direction. With this shock absorbing mechanism 49A, the shock absorbing ability can be increased.

2] The shock absorbing mechanism 49, 49A may be a variable orifice capable of adjusting the flow rate of oil flowing through the orifice 40, and the flow rate may be adjusted according to the weight of the occupant.
3] The airbag moving mechanism 21 may be normally operated by operating a button provided in the vehicle to move the steering wheel 2 so that the position of the steering wheel 2 can be adjusted. In this case, in the state where the steering wheel 2 is positioned at the second position, the steering wheel 2 is moved to the first position as necessary in the event of a vehicle collision, for example, when the estimated impact force at the time of the vehicle collision is small. You may make it move to.

4] As a configuration in which the airbag 31 is selectively deployed in either the first deployed state or the second deployed state, the tether fixing / releasing mechanism 33 is omitted, and the amount of gas generated by the inflator 32 is changed to the first This may be realized by selecting one of the gas amount and the second gas amount smaller than the first gas amount.
5] The airbag 31 is configured so as to be selectively deployed in, for example, one of three sizes of large, medium, and small (or a plurality of levels of four or more), and then the first deployed state And the second expanded state may be set.

6] An electric motor may be applied instead of the hydraulic cylinder 22 as the actuator of the airbag moving mechanism 21. In this case, the hydraulic pressure supply device 23 can be omitted, and the responsiveness of moving the steering wheel 2 can be improved.
7] The airbag unit 20 may be configured to be separable from the steering wheel 2, and the airbag moving mechanism 21 may be configured to move only the airbag unit 20 between the first position and the second position. . In this case, the airbag device 5 can be applied not only for the driver's seat but also for the passenger seat and the rear seat.

8] When an occupant state sensor capable of detecting the size, seat position, posture, etc. of the occupant is provided in the vehicle and electrically connected to the ECU 6, in particular, in S10 of FIG. 6, the steering wheel 2 is moved in the second direction. Based on the sensor signal from the occupant state sensor, the maximum value for moving the steering wheel 2 and the moving speed of the steering wheel 2 in the second direction may be set. Further, a seat front / rear position detection sensor may be provided, and the maximum or moving speed may be set according to the front / rear position of the seat.

9] In addition, various modifications can be added and implemented without departing from the spirit of the present invention, and the present invention can also be applied to various vehicles other than automobiles.

It is explanatory drawing of the steering apparatus and airbag apparatus which were mounted in the motor vehicle based on the Example of this invention. It is a block diagram of the control staff of a steering apparatus and an airbag apparatus. It is a side view of the steering wheel of the 1st position, and the air bag developed to the 1st state. FIG. 6 is a side view of the steering wheel at the first position and the airbag deployed in the second state. The steering wheel in the second position and the airbag deployed in the second state. It is sectional drawing of a tether fixing / releasing mechanism. It is operation | movement explanatory drawing of an airbag moving mechanism (movement stop state). It is operation | movement explanatory drawing of an airbag moving mechanism (moving state to a 1st direction). It is action | operation explanatory drawing of an airbag moving mechanism (moving state to a 2nd direction). It is a flowchart of airbag control. It is a flowchart of airbag control. It is a flowchart of the misprediction process of airbag control. It is explanatory drawing of the airbag control in case of impact force: large and avoidance steering: None. It is explanatory drawing of the airbag control in case of impact force: large and avoidance steering: None. It is explanatory drawing of the airbag control in case impact force: large, avoidance steering: exists. It is explanatory drawing of airbag control in case impact force: large, avoidance steering: exists. It is explanatory drawing of the airbag control in the case of impact force: small. It is explanatory drawing of the airbag control in the case of steering angle in small prediction: small. It is explanatory drawing of the airbag control in the case of steering angle in large misprediction: Large and vehicle speed: High-> Low. It is explanatory drawing of the airbag moving mechanism containing the impact-absorbing mechanism which concerns on a change form.

Explanation of symbols

1 Automobile 2 Steering wheel 3 Front wheel 4 Steering device 5 Airbag device 6 ECU
10 STG Steering Angle Sensor 20 Airbag Unit 21 Airbag Movement Mechanism 24 Vehicle Speed Sensor 25 Collision Sensor 26 Distance Sensor 27 STG Position Sensor 28 Occupant Weight Sensor 31 Airbag 32 Inflator 33 Tether Fixing / Release Mechanism 49, 49A Shock Absorption Mechanism

Claims (11)

In a vehicle equipped with a steering device that controls the steering angle of a steerable wheel based on a steering angle signal of a steering wheel,
An airbag unit provided on the steering wheel and having an airbag that can be deployed rearward in the event of a vehicle collision;
Collision detection means for detecting a collision of the vehicle;
Airbag deployment means for deploying an airbag when the collision detection means detects a vehicle collision;
Airbag moving means for moving the airbag unit over a predetermined first position and a second position closer to the occupant than the first position;
A collision prediction means for predicting a collision of the vehicle;
An airbag movement control means for controlling the airbag moving means to move the airbag unit from the first position to the second position when the collision prediction means predicts a vehicle collision;
An air bag device for a vehicle, comprising:   2. An impact absorbing means for absorbing an impact force received from an occupant acting on an airbag moving means at the time of a vehicle collision by moving the airbag unit from the second position to the first position is provided. The vehicle airbag device described in 1. The airbag deployment means is configured to be deployed alternatively to either the first deployed state or the second deployed state in which the airbag is deployed with a smaller deployment force than the first deployed state,
The airbag deployment means deploys the airbag to the first deployed state when the airbag unit is positioned at the first position at the time of a vehicle collision, and the airbag unit is positioned at the second position at the time of the vehicle collision. 2. The vehicle airbag device according to claim 1, wherein the airbag is deployed in a second deployed state.   When the impact force received by the occupant at the time of the vehicle collision is smaller than a predetermined value, even when the airbag unit is located at the first position at the time of the vehicle collision, the airbag deployment means puts the airbag in the second deployed state. The vehicle airbag device according to claim 3, wherein the vehicle airbag device is deployed. An impact force estimation means is provided for estimating the impact force received by a passenger at the time of a vehicle collision,
The airbag movement control means prohibits the movement of the airbag unit to the second position when the impact force estimated by the impact force estimation means is smaller than a predetermined value. The airbag apparatus for vehicles as described.   When the collision prediction means predicts a vehicle collision, the airbag movement control means prohibits the movement of the airbag unit to the second position when the steering angle of the steering wheel is greater than or equal to a predetermined value. The vehicle airbag device according to claim 1. An erroneous prediction detection means capable of detecting whether a collision of the vehicle predicted by the collision prediction means has actually occurred;
When the erroneous prediction detection means detects that a vehicle collision has not actually occurred, the airbag movement control means is located at the second position when a predetermined return condition is satisfied. The vehicle airbag device according to claim 1, wherein the airbag unit is moved back to the first position.   The vehicle airbag device according to claim 7, wherein the predetermined return condition includes a condition that a steering angle of a steering wheel is smaller than a predetermined value.   9. The vehicle airbag device according to claim 8, wherein the predetermined return condition includes a condition that the vehicle speed is smaller than a predetermined value.   2. The vehicle airbag device according to claim 1, wherein, when the collision prediction unit predicts a vehicle collision, the steering angle of the wheel is maintained after the airbag unit starts to move. . 11. The airbag unit according to claim 1, wherein an airbag unit is integrally provided on the steering wheel, and the airbag moving means moves the airbag unit together with the steering wheel between a first position and a second position. The airbag apparatus for vehicles in any one.