JP2010143243A - Occupant crash protection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To operate an occupant protecting means at an appropriate timing regardless of difference in build of an occupant. <P>SOLUTION: Based on the transition of the head position of the occupant in a vehicle, a changeover in the displacing direction of the head of the occupant is determined. Corresponding to this determination timing, the force of constraint to the seat S of the occupant is further enhanced by a seat belt mechanism (an irreversible seat belt mechanism), and an air bag body 41 is deployed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an occupant protection device.

Conventionally, from the viewpoint of occupant protection, a method for detecting a rollover of a vehicle has been proposed (see, for example, Patent Document 1). According to this method, when the roll rate detected by the roll rate sensor exceeds the threshold value and the relationship between the lateral acceleration and the roll angle is within the determination region, it is determined that the roll over is made. When it is determined that the vehicle is overturned, occupant protection means such as a head protection airbag device is operated.
Japanese Patent Laid-Open No. 2000-9599

  By the way, according to the technique disclosed in Patent Document 1, rollover is determined based on the motion state of the vehicle, and the occupant protection means is operated uniformly regardless of variations in the physique difference of the occupants. However, since the behavior of the occupant in the vehicle at the time of rollover differs depending on the variation in the physique of the occupant, there is a possibility that the occupant protection means cannot be operated at an appropriate timing.

  The present invention has been made in view of such circumstances, and an object thereof is to operate the occupant protection means at an appropriate timing regardless of the physique difference of the occupants.

  In order to solve this problem, the occupant protection device of the present invention provides occupant protection means corresponding to the timing at which the change of the displacement direction of the occupant head is determined based on the transition of the occupant head position in the vehicle. Make it work.

  According to the present invention, since the occupant protection means is operated in response to the timing at which the change of the displacement direction of the head position is determined, the occupant protection means is operated at an appropriate timing for each occupant regardless of the physique difference. be able to. Thereby, a passenger | crew can be protected appropriately.

(First embodiment)
FIG. 1 is an explanatory diagram illustrating a vehicle to which an occupant protection device according to the first embodiment of the present invention is applied and a state of an occupant riding the vehicle. This occupant protection device is a device that protects an occupant seated on the seat S when the vehicle rolls over (in this embodiment, rollover), and particularly a vehicle structure (for example, a center) that forms an occupant space. Suppresses occupant head contact with pillars and side windows.

  Here, in the present specification, a pair of seats S (a right seat S positioned on the right side and a left seat S positioned on the left side with respect to the traveling direction of the vehicle) and an occupant seated thereon are identified. Therefore, the terms far side and near side are used as necessary. Here, the far side means a side where the wheel is lifted by an increase in the inclination of the vehicle at the time of rollover (including a scene where there is a possibility of rollover). On the other hand, the near side refers to the side opposite to the far side. Specifically, the near side refers to the side where the wheel continues to come into contact with the ground at the time of rollover longer than the far side wheel. For example, at the time of clockwise rollover, specifically, when the vehicle rolls clockwise as viewed from the occupant seated on the seat S, the right seat S and the occupant seated on it correspond to the near-side seat S and the near-side occupant. The left seat S and the occupant seated thereon correspond to the far side seat S and the far side occupant.

  FIG. 2 is an explanatory diagram schematically showing the configuration of the occupant protection device. This occupant protection device mainly includes a seat S and various support portions 11 to 16 provided on the vehicle structure, a seat belt mechanism 20, a side airbag unit 40, and a control portion 50 (see FIG. 5 described later). It is configured.

  The seat S includes a seat back Sb that supports the back from the occupant's waist, a headrest Sh that supports the head of the occupant, and a seat cushion Sc that supports the thigh and buttocks of the occupant. The seat back Sb and the seat cushion Sc have a built-in movable mechanism fixed to a main frame (not shown) that functions as a skeleton, so that a part of the seat back Sb and the seat cushion Sc will be described later. Can be moved freely. The basic configuration of the seat S is the same regardless of the near side and the far side.

  The lumbar support portions 11 and 12 are provided in the vicinity of the waist of the occupant seated on the seat S and in the left and right side regions constituting the seat back Sb. The main frame accommodated in the seat back Sb is provided with a movable frame configured to be swingable in the front-rear direction within a predetermined angle range at a position corresponding to the lumbar support portions 11 and 12. Each movable frame is connected to an actuator 55 (see FIG. 5 to be described later), and swings when the actuator 55 is driven. The movable frame is set at a rear position in a normal state (initial state), and by operating the movable frame from the rear to the front, the lumbar support portions 11 and 12 are bent toward the front inner side (occupant side), The support performance in the vicinity of the occupant's waist can be improved. The actuator 55 that operates the lumbar support portions 11 and 12 employs a reversible actuator that is reversibly driven such as an electric motor. As a result, the lumbar support portions 11 and 12 are also operated in a reversible manner. It is possible to return to the normal state from the state of operating inward. One lumbar support portion 11 is disposed in the right region of the seat back Sb, and the other lumbar support portion 12 is disposed in the left region of the seat back Sb. The individual lumbar support portions 11 and 12 are independent. (See, for example, FIG. 3). Thus, the individual lumbar support portions 11 and 12 have a function of reversibly restraining the lateral movement of the occupant's waist (lumbar support means).

  The rhino support portions 13 and 14 are provided in the left and right side regions constituting the seat cushion Sc, respectively. The main frame housed inside the seat cushion Sc is provided with a movable frame configured to be swingable in the vertical direction within a predetermined angle range at a position corresponding to the cy-support portions 13 and 14. Each movable frame is connected to an actuator 56 (see FIG. 5 to be described later), and swings when the actuator 56 is driven. The movable frame is set at a lower position in a normal state (initial state), and by operating the movable frame from the lower side to the upper side, the rhino support portions 13 and 14 of the seat cushion Sc are moved upward (to the occupant side). The support performance in the vicinity of the occupant's thigh can be improved. The actuator 56 for operating the siport units 13 and 14 employs a reversible actuator that is reversibly driven such as an electric motor. It is possible to return to the normal state from the state that has been operated. One rhino support part 13 is arranged on the right side of the seat cushion Sc, the other rhino support part 14 is arranged on the left side of the seat cushion Sc, and the individual rhino support parts 13 and 14 are independently provided. It can operate (see, for example, FIG. 3). As described above, each of the cyport parts 13 and 14 has a function of reversibly restraining the movement of the occupant's thigh in the lateral direction (thy support means).

  The knee support portions 15 and 16 are provided at each of the door and the center console so as to face each other at a height corresponding to the knee portion of the occupant seated on the seat S. Each knee support portion 15, 16 is configured to be able to protrude in the occupant direction, and is connected to an actuator 57 (not shown) (see FIG. 5 described later). By driving this actuator 57, the occupant Protrusively toward the side. The knee support portions 15 and 16 constitute part of the surface shape of the inner panel of the door or the center console in a normal state (initial state), and project toward the occupant side by operating toward the occupant side. To do. Thereby, the end performance of knee support parts 15 and 16 can aim at improvement of the support performance near a knee part because it contacts a crew member's knee part. The actuator 57 that operates the knee support portions 15 and 16 employs a reversible actuator that is reversibly driven such as an electric motor. As a result, the knee support portions 15 and 16 can also be reversibly operated as passengers. It is possible to return to the normal state from the state protruding to the side. One knee support portion 15 is disposed on the right side with respect to the occupant, and the other knee support portion 16 is disposed on the left side with respect to the occupant. The individual knee support portions 15 and 16 are independently provided. It can operate (see, for example, FIG. 3). As described above, the individual knee support portions 15 and 16 have a function of reversibly restraining the movement of the occupant's legs in the lateral direction (knee support means).

  The seat belt mechanism 20 is mainly composed of a retractor 21 and a webbing 22. The retractor 21 is disposed at the lower end of the center pillar, and one end of the webbing 22 is locked to the take-up shaft (not shown) of the retractor 21. The other end of the webbing 22 is fixedly attached to a bracket on the floor via a shoulder anchor 23 attached to the upper part of the center pillar.

  A tongue 25 is attached between the end of the webbing 22 on the bracket side and the shoulder anchor 23 so as to be movable along the extending direction of the webbing 22. An occupant seated on the seat S (for example, the occupant of the right seat S) pulls the webbing 22 out of the retractor 21 and passes the tongue 25 from the left side to the right side on its own thigh and is attached to the floor. The inner buckle 24 is engaged. The inner buckle 24 and the tongue 25 can be detachably engaged. Accordingly, the webbing 22 reaches the bracket from the retractor 21 via the shoulder anchor 23, the occupant's right shoulder, the occupant's left waist, the tongue 25, and the occupant's thigh.

  In the normal state (initial state), the retracting shaft of the retractor 21 is given a rotational force so as to wind up and store the webbing 22 by an urging means such as a spring. As a result, the webbing 22 is drawn to the retractor 21 side with a predetermined pull-in amount (reference pull-in amount). Further, the winding shaft of the retractor 21 can apply a rotational force so as to wind up and store the webbing 22 by driving a belt actuator 58 (see FIG. 5 described later). As a result, when a deceleration greater than a certain level is applied to the vehicle, the belt actuator 58 applies a larger rotational force to the take-up shaft than the normal pull-in amount when the vehicle rolls over. The webbing 22 is pulled toward the retractor 21 with a large pull-in amount. As a result, it becomes difficult to pull out the webbing 22, and the body movement of the occupant is restrained by the tensioned webbing 22 during a collision or sudden deceleration.

  In the present embodiment, the belt actuator 58 includes, for example, a reversible actuator that is reversibly driven such as an electric motor and a nonreciprocal actuator that is irreversibly driven such as an explosive pretensioner. The nonreciprocal actuator has a feature that a large rotational force can be instantaneously applied to the winding shaft as compared with the reversible actuator due to its property. Normally (for example, a scene in which a deceleration exceeding a certain level acts on the vehicle), the belt actuator 58 is driven mainly by a reversible actuator, but in a case where the passenger is restrained instantaneously (for example, at the time of rollover) A non-reversible actuator is driven.

  Hereinafter, for convenience of description, when driving a reversible actuator of the belt actuator 58, the seat belt mechanism 20 is referred to as a reversible seat belt mechanism 20, and when driving a non-reversible actuator of the belt actuator 58, the seat The belt mechanism 20 is referred to as a reversible seat belt mechanism 20. In other words, the reversible seat belt mechanism 20 has a function of reversibly restraining the occupant (reversible seat belt means), and the irreversible seat belt mechanism 20 has a function of irreversibly restraining the occupant. (Non-reversible seat belt means).

  A rearview mirror 30 is attached to the front center of the roof panel of the vehicle. As shown in FIG. 4, the rearview mirror includes a mirror main body 31 to which a mirror (not shown) is attached, and a camera stay 32 attached to the lower end portion of the mirror main body 31. A pair of cameras 33 are attached to the camera stay 32. One camera 33 includes the head of an occupant seated on the right seat S, and the other camera 33 includes the head of the occupant seated on the left seat S. Each scene is imaged.

  The side airbag unit 40 includes an airbag actuator 58 (see FIG. 5 to be described later) that is irreversibly driven, such as an inflator, and an airbag main body 41. In the present embodiment, Specifically, it is an airbag unit attached to each side roof rail SR (airbag means). 2 and 4, the airbag unit 40 is drawn only on the right seat S side, but the side airbag unit 40 is also attached to the side roof rail side on the left seat S side.

  The side roof rail SR extends along the front-rear direction at the upper part of the front pillar, the center pillar, and the rear pillar. The side roof rail SR is provided with a substantially U-shaped cover (not shown), and a bag-like airbag body 41 is housed in a folded state inside the cover. The upper portion of the airbag body 41 is fastened to the side roof rail SR together with the cover by means of a bolt or the like that is a cover mounting member. The rear end portion of the airbag body 41 is connected to the inflator. The airbag main body 41 is normally housed in a cover, and in operation, the inflator is ignited to generate an inert gas, which is inflated and deployed by this gas pressure. When the cover is opened downward as the airbag body 41 is inflated, the airbag body 41 is deployed from the side roof rail SR in a curtain shape between the occupant and the vehicle body member. Thus, the side airbag unit 40 has a function of irreversibly deploying the airbag body 41 on the vehicle door side.

  FIG. 5 is a block configuration diagram of the occupant protection device centered on the control unit 50. As the control unit 50, a microcomputer mainly composed of a CPU, a ROM, a RAM, and an input / output interface can be used. The control unit 50 performs various calculations in accordance with a control program stored in the ROM, thereby controlling the various actuators 55 to 59, the various support units 11 to 16, the seat belt mechanism 20 (reversible and irreversible seats). The state of the belt mechanism 20) and the side airbag unit 40 is controlled. Information from various sensors 51 to 53 for detecting the motion state of the vehicle and the like is input to the control unit 50.

  The seat sensor 51 is provided in each of the right seat S and the left seat S, and detects the presence or absence of a seated occupant. As the seat sensor 51, a pressure sensor or the like built in the seat cushion Sc can be used. The roll rate sensor 52 is a sensor that detects a rotational angular velocity (hereinafter referred to as “roll rate”) in the roll direction of the vehicle (motion state detecting means). The control unit 50 can specify the roll angle of the vehicle based on the roll rate obtained from the roll rate sensor 52. The roll angle may also be detected by providing a sensor such as a gyro. The lateral acceleration sensor 53 is a sensor that detects lateral (vehicle width direction) acceleration acting on the vehicle (motion state detecting means).

  The camera 33 captures a scene including the head of the occupant seated on each seat S. Thereby, the camera 33 detects indirectly the head position of the passenger | crew in a vehicle (position detection means).

  In relation to the present embodiment, the control unit 50 performs image processing on an image input from the camera 33, and thereby specifies (detects) the head position of the occupant in the vehicle. Based on the detected transition of the head position, the control unit 50 operates the occupant protection means in response to the timing when the change of the displacement direction of the occupant head is determined (control means). This occupant protection means suppresses the contact of the occupant head with the vehicle structure forming the occupant space. In the present embodiment, the irreversible seat belt mechanism 20 and the side airbag unit 40 correspond to this. To do.

  Further, the control unit 50 predicts the rollover of the vehicle in advance based on the vehicle motion state such as the roll angle, the roll rate, and the lateral acceleration (prediction means). In this case, after the vehicle rollover is predicted, the control unit 50 operates the occupant protection means in response to the timing at which the change of the displacement direction of the occupant head is determined.

  Further, the control unit 50 operates the restraining means at the timing when the vehicle rollover is predicted. This restraining means restrains the posture change of the occupant, and in the present embodiment, the various support portions 11 to 16 and the reversible seat belt mechanism 20 correspond to this.

  FIG. 6 is a flowchart showing a series of procedures for the passenger protection processing according to the first embodiment of the present invention. The processing shown in this flowchart is executed by the control unit 50 at predetermined intervals.

  First, in step 1 (S1), the control unit 50 reads sensor values detected by the various sensors 51 to 53 and a captured image captured by the camera 33. At this time, the control unit 50 calculates the roll angle of the vehicle by time-integrating the roll rate detected by the roll rate sensor 52. In addition, the control unit 50 performs image processing on an image input from the camera 33, thereby identifying (detecting) the position of the head of the occupant in the vehicle. The head position of the occupant indicates the position of the head relative to a reference point (for example, headrest Sh) in the vehicle, and the head movement to the inside of the rotation center of the vehicle is positive. That is, the far-side occupant is specified as a positive value when the head moves in the vehicle center direction, and the near-side occupant is specified as a positive value when the head moves toward the vehicle door.

  In step 2 (S2), the control unit 50 predicts a rollover of the vehicle based on the roll angle and the roll rate read in step 1. As shown in FIG. 7, the controller 50 is in a situation where the vehicle may roll over (rollover region (region A)) or in a situation where there is no possibility of rollover (non-rolling). A map for specifying the over region (region B)) from both the relationship between the roll angle Ar and the roll rate Rr is held. This map calculates the rollover area and non-roll by calculating whether the vehicle rolls over or not through various experiments and simulations when the relationship between the various roll angles Ar and roll rate Rr continues. The over-area relationship is defined and held in the ROM of the control unit 50. The control unit 50 refers to this map. When the relationship between the current roll rate Rr and the roll angle Ar is included in the region A, the control unit 50 predicts the rollover of the vehicle, and the relationship between the two is included in the region B. If it does, predict that it will not roll over. In addition, in addition to the roll angle Ar and the roll rate Rr, the lateral acceleration can be taken into consideration for the prediction of the rollover.

  If an affirmative determination is made in step 2, that is, if the relationship between the roll angle Ar and the roll rate Rr is included in the rollover area A, the process proceeds to step 3 (S3). On the other hand, if a negative determination is made in step 2, that is, if the relationship between the roll angle Ar and the roll rate Rr is included in the non-rollover region B, the present routine is exited. In the case where the negative determination is made in step 2, when the support process shown in step 4 (S4) described later is performed, the control unit 50 ends the support process and returns the restraint means to the initial state. Then exit this routine.

  In step 3, the control unit 50 specifies the roll direction after referring to the motion state of the vehicle. As the roll direction is specified, the control unit 50 can specify which of the right sheet S side and the left sheet S side corresponds to the near side or the far side. Hereinafter, for convenience of description, the description will be made on the assumption that the vehicle rolls clockwise as viewed from the occupant seated on the seat S. In this case, the right seat S corresponds to the near side, and the left seat S corresponds to the far side.

  In step 4 (S4), the control unit 50 performs support processing. This support process is performed in order to suppress disturbance generated in the displacement of the occupant's head by restraining the occupant's posture change. As specific support processing contents, the following processing is performed. The control unit 50 outputs a drive signal to the lumbar support actuator 55 to drive the lumbar support actuator 55. As the lumbar support actuator 55 is driven, the lumbar support portions 11 and 12 are bent. In addition, the control unit 50 outputs a drive signal to the cysupport actuator 56 to drive the cysupport actuator 56. As the thysupport actuator 56 is driven, the cysupport portions 13 and 14 bend. Similarly, the control unit 50 outputs a drive signal to the knee support actuator 57 to drive the knee support actuator 56. As the knee support actuator 56 is driven, the knee support portions 15 and 16 project. Further, the control unit 50 outputs a drive signal to the electric motor (reversible actuator) that is the belt actuator 58 to drive the electric motor. As the electric motor is driven, the webbing 22 is retracted toward the retractor 21 with a retraction amount larger than the reference retraction amount by applying a larger rotational force than usual to the take-up shaft of the retractor 21. Note that these support processes need only operate the support portions 11 to 16 located on the near side with reference to individual occupants, and do not necessarily require the support portions 11 to 16 on both sides to operate.

  In step 5 (S5), the control unit 50 determines whether an occupant is seated on the right seat S based on the detection result of the seat sensor 51. If an affirmative determination is made in step 5, the process proceeds to step 6 (S6). On the other hand, if a negative determination is made in step 5, the process proceeds to step 7 (S7).

  In step 6, the control unit 50 determines whether an occupant is seated on the left seat S based on the detection result by the seat sensor 51. If a negative determination is made in step 6, the process proceeds to step 8 (S8). On the other hand, if a negative determination is made in step 6, the process proceeds to step 9 (S9).

  In step 7, the control unit 50 performs the occupant protection process on the far side on the assumption that the occupant is seated on the left side seat S on the far side. FIG. 8 is a flowchart showing a far-side occupant protection processing routine. First, in step 70 (S70), the control unit 50 detects the head position Xf (t) of the occupant located on the far side based on the captured image output from the camera 33.

  In step 71 (S71), the control unit 50 determines whether or not the currently detected head position Xf (t) and the previously detected head position Xf (t-1) satisfy the following relational expression. Judging.

(Formula 1)
Xf (t) −Xf (t−1) ≦ 0
From Expression 1, it is determined whether the value obtained by subtracting the head position Xf (t−1) at the timing earlier than the current head position Xf (t) is equal to or less than zero. According to this relational expression, based on the transition of the head position Xf of the occupant on the far side, as shown in FIG. 9, the displacement direction of the occupant head is changed (reversed), that is, from the vehicle center direction to the door side. Conversion is judged.

  If an affirmative determination is made in step 71, that is, if a change in the displacement direction of the head position is determined, the process proceeds to step 72 (S72). On the other hand, if a negative determination is made in step 71, that is, if there is no change in the displacement direction of the head position, the process proceeds to step 73 (S73).

  In step 72, the control unit 50 operates the irreversible seat belt mechanism 20 and the side airbag unit 40 related to the left seat S from the viewpoint of occupant protection against rollover. Specifically, the control unit 50 outputs a drive signal to an explosive pretensioner (irreversible actuator) that is the belt actuator 58, and drives the explosive pretensioner. As the gunpowder type pretensioner is driven, the webbing 22 is pulled into the retractor 21 side instantaneously and for a predetermined period by momentarily applying a rotational force larger than normal to the take-up shaft of the retractor 21. The pull-in amount of the webbing 22 by the explosive pretensioner is set to a value larger than that in the support process. Further, the control unit 50 outputs a drive signal to the inflator that is the side airbag actuator 59 to drive the inflator. As the inflator is driven, the airbag body 41 of the side airbag unit 40 is deployed for a predetermined period.

  In step 73, the control unit 50 updates the past head position Xf (t-1) with the currently detected head position Xf (t).

  Referring to FIG. 6 again, in step 8, the control unit 50 performs occupant protection processing on the near side on the assumption that the occupant is seated on the right side seat S on the near side. FIG. 10 is a flowchart showing a near-side occupant protection processing routine. First, in step 80 (S80), the control unit 50 detects the head position Xn (t) of the occupant located on the near side based on the captured image output from the camera 33.

  In step 81 (S81), the control unit 50 determines whether or not the currently detected head position Xn (t) and the previously detected head position Xn (t-1) satisfy the following relational expression. Judging.

(Formula 2)
Xn (t) -Xn (t-1) <0
According to Equation 1, it is determined whether the value obtained by subtracting the head position Xn (t−1) at the timing earlier than the current head position Xn (t) is smaller than zero. According to this relational expression, based on the transition of the head position Xn of the far-side occupant, a change in the displacement direction of the occupant head, that is, a change from the door direction to the vehicle center direction is determined.

  If an affirmative determination is made in step 81, that is, if a change in the displacement direction of the head position is determined, the process proceeds to step 82 (S82). On the other hand, if a negative determination is made in step 81, that is, if there is no change in the displacement direction of the head position, the process proceeds to step 83 (S83).

  In step 78, the control unit 50 operates the irreversible seat belt mechanism 20 and the side airbag unit 40 related to the right seat S from the viewpoint of occupant protection against rollover. Specifically, the control unit 50 outputs a drive signal to an explosive pretensioner (irreversible actuator) that is the belt actuator 58, and drives the explosive pretensioner. As the gunpowder type pretensioner is driven, the webbing 22 is pulled into the retractor 21 side instantaneously and for a predetermined period by momentarily applying a rotational force larger than normal to the take-up shaft of the retractor 21. The pull-in amount of the webbing 22 by the explosive pretensioner is set to a value larger than that in the support process. Further, the control unit 50 outputs a drive signal to the inflator that is the side airbag actuator 59 to drive the inflator. As the inflator is driven, the airbag body 41 of the side airbag unit 40 is deployed for a predetermined period.

  In step 83, the control unit 50 updates the past head position Xn (t-1) with the currently detected head position Xn (t).

  Referring again to FIG. 6, in step 8, the control unit 50 performs the irreversible seat belt mechanism 20 and the side airbag unit 40 related to the left seat S and the right seat S from the viewpoint of occupant protection against rollover. The irreversible seat belt mechanism 20 and the side airbag unit 40 are operated. In the individual processes relating to the far side and the near side, the processes shown in steps 7 and 8 are performed in parallel.

  FIG. 11 is a timing chart showing the transition of the head position Xf of the occupant on the far side. In the same figure, (a) shows a time-dependent transition of the occupant's head position Xf, and when the head is displaced toward the center of the vehicle, the position is shown as a positive value. (B) shows the transition of the roll rate Rr, and (c) shows the transition of the roll angle Ar. Further, (d) shows the operation timing of the irreversible seat belt mechanism 20 and the side airbag unit 40 in the occupant protection process.

  As shown in the figure, when the vehicle rolls with turning or the like, the head of the far-side occupant moves toward the center of the vehicle by centrifugal force. When rollover is predicted at timing Tss, support processing is executed. At this timing, the occupant protection process by the irreversible seat belt mechanism 20 and the side airbag unit 40 is not executed. Next, when the vehicle rolls over, the head of the occupant heads in the reverse direction (door direction). At this time, the change of the displacement direction of the occupant's head position is determined. Then, at this timing Tso, occupant protection processing by the irreversible seat belt mechanism 20 and the side airbag unit 40 is executed, and restraint by the webbing 22 and deployment of the airbag body 41 are continued until a predetermined period until timing Ten. Thereby, contact with a vehicle structure and a crew member's head is controlled.

  FIG. 12 is a timing chart showing the transition of the head position Xn of the near-side occupant. In the figure, (a) shows a time-dependent transition of the occupant's head position Xn, and when the head is displaced in the door direction, the position is shown as a positive value. (B) shows the transition of the roll rate Rr, and (c) shows the transition of the roll angle Ar. Further, (d) shows the operation timing of the irreversible seat belt mechanism 20 and the side airbag unit 40 in the occupant protection process.

  As shown in the figure, when the vehicle rolls with turning or the like, the head of the near-side occupant moves in the direction of the door by centrifugal force, and then the movement is restricted by the door. When rollover is predicted at timing Tss, support processing is executed. At this timing, the occupant protection process by the irreversible seat belt mechanism 20 and the side airbag unit 40 is not executed. Next, when the vehicle rolls over, the head of the occupant goes in the reverse direction (vehicle center direction). Thereby, the change of the displacement direction of a passenger | crew's head position is judged (point P1). Then, at this timing Tso, occupant protection processing by the irreversible seat belt mechanism 20 and the side airbag unit 40 is executed. In addition, the transition to the point P1, the passenger's head is displaced toward the center of the vehicle, but is then displaced again to the door side before the vehicle roof contacts the ground. By the occupant protection process, the restraint by the webbing 22 and the deployment of the airbag main body 41 are continued for a predetermined period until the timing Ten, whereby the contact between the vehicle structure and the occupant head is suppressed.

  FIG. 13 is a timing chart showing the transition of the head position Xf of the occupant on the far side. Each parameter shown in the figure is the same as that shown in FIG. 11, but in this figure, although a rollover is predicted, a timing chart of a scene where the rollover is avoided is shown.

  As shown in the figure, when the vehicle rolls as the vehicle turns, the far-side occupant moves its head toward the center of the vehicle by centrifugal force. When the rollover is predicted based on the vehicle motion state at the timing Tss, the support process is executed. At this timing, the occupant protection process by the irreversible seat belt mechanism 20 and the side airbag unit 40 is not executed. Next, when the vehicle rollover is avoided, the roll rate Rr and the roll angle Ar decrease, and the relationship between the two transitions to the non-rollover region B (see FIG. 7). In this case, the control unit 50 stops the support process, and returns the various support units 11 to 16 and the reversible seat belt mechanism 20 that are the restraining means from the restrained state to the normal state (unconstrained state).

  Thus, according to the present embodiment, the occupant protection device determines the change of the displacement direction of the occupant head based on the transition of the occupant head position in the vehicle. Then, the irreversible seat belt mechanism 20 and the side airbag unit 40, which are occupant protection means, are operated in accordance with this determination timing. Specifically, the occupant's restraining force on the seat S is further increased by the irreversible seat belt mechanism 20, and the airbag body 41 is deployed.

  In the conventional method, rollover is predicted based on the roll rate and roll angle (timing Tss shown in FIGS. 11 to 13), and the occupant protection means is operated in accordance with this prediction timing. However, in this embodiment, this operation timing is delayed until the timing at which the displacement direction of the head position changes. For this reason, the time from the operation start timing until the vehicle roof contacts the ground, that is, the operation period of the occupant protection means can be reduced. This makes it possible to reduce the size of an irreversible actuator such as an inflator.

  In addition, the head behavior of the occupant during the rollover may vary depending on the physique difference such as the height of the occupant. As indicated by the solid line, the broken line, and the alternate long and short dash line in FIG. 11, the relative amount of change in the head position differs depending on the physique difference, but the displacement shows the same tendency. Therefore, by monitoring the transition of the head position, it is possible to appropriately specify the conversion timing for each occupant. Thereby, it becomes possible to determine the timing at which the occupant head is displaced toward the vehicle structure regardless of the physique difference of the occupant, and the occupant protection means can be operated at an appropriate timing. Therefore, it is possible to appropriately protect the occupant. In addition, in FIG. 11, a continuous line shows transition of the head position of an occupant having an average physique, a broken line shows transition of the head position of an occupant having a height higher than that, and a one-dot chain line indicates Also shows the transition of the head position of passengers with short stature.

  In addition, since the occupant protection means is operated based on the change of the head position, in the case where the rollover is predicted but the rollover is actually avoided, the operation of the occupant protection means is also avoided. Is done. As a result, unnecessary operations can be suppressed, and reliability can be improved. Moreover, the operation | movement of the irreversible seatbelt mechanism 20 and the side airbag unit 40 as a passenger | crew protection means drives a irreversible actuator (an explosive pretensioner and an inflator). Unlike the reversible actuator, the non-reversible actuator employs a configuration that does not return to the initial state once used. Therefore, by determining based on the change of the head position, in a scene where rollover is actually avoided, driving of the nonreciprocal actuator is avoided. As a result, it is possible to suppress the repair accompanying the replacement of the irreversible actuator and the situation where the repair cost increases.

  In the present embodiment, the occupant protection device operates the restraining means at the timing when the vehicle rollover is predicted. Specifically, the restraining force of the occupant on the seat S is increased more than usual by the reversible seat belt mechanism 20, and the waist, thigh and knee are restrained by the various support portions 11 to 16, thereby The posture change of the occupant is restrained.

  According to this configuration, the occupant is restrained from moving forward by restraining the occupant to the seat S by the webbing 52. Thereby, a passenger | crew's movement of the left-right direction can be made more remarkable. Further, as shown by S1 in FIG. 14A, the lumbar support portions 11 and 12 suppress the movement toward the vehicle center side due to the skidding of the occupant's waist. Thereby, it becomes easy to rotate a passenger | crew's upper body part centering | focusing on a waist | hip | lumbar part, and the movement of a passenger | crew's head in the left-right direction can be made more remarkable (refer FIG.14 (b)). Therefore, it is possible to detect the change of the displacement direction of the occupant head more accurately. Moreover, by using together the cy-support parts 13 and 14 that hold the occupant's thighs and the knee support parts 15 and 16 that hold the limbs of the occupant, the rotational behavior of the upper part of the occupant is further amplified, As a result, the movement of the occupant's head in the left-right direction becomes more obvious. Thereby, it is possible to detect the change of the occupant head even more accurately.

  Moreover, in this embodiment, by using a reversible actuator, each restraining means can return from the restrained state to the unconstrained state in a case where rollover is avoided after predicting rollover.

  Further, according to the present embodiment, the occupant protection device determines the change of the displacement direction of the head position by using different logics for the far-side occupant and the near-side occupant. According to such a configuration, it is possible to determine the change by paying attention to the head behavior of each occupant, so that the occupant protection means can be operated at an appropriate timing.

  In the present embodiment, the near-side occupant is determined to change when the condition shown in Formula 2 is satisfied, but the present invention is not limited to this. For example, as shown in FIG. 12, the change may be determined at the timing of point P2. The head behavior of the occupant on the near side is displaced from the door side to the center of the vehicle and is displaced again to the door side before the vehicle roof is set. Therefore, the occupant protection means may be operated at the switching timing from the vehicle center to the door side. Similarly to the far side, based on the condition shown in Formula 1, the change may be determined at the timing of point P3 as shown in FIG. This timing has an advantage that the operation timing can be set according to the physique difference of the occupant, although the operation start of the occupant protection means is earlier than the timing indicated by the point P1. Therefore, it is possible to appropriately determine the operation timing as compared with the method of setting the operation timing uniformly at the rollover prediction timing as in the conventional method.

(Second Embodiment)
The occupant protection device according to the second embodiment is different from that of the second embodiment in a method for determining the change of the displacement direction of the head position. The system configuration of the occupant protection device, the procedure of occupant protection processing, and the like are the same as those in the first embodiment, and the following description will focus on differences.

  FIG. 15 is an explanatory diagram of a head position change determination according to the second embodiment. In the present embodiment, the control unit 50 reverses the conversion based on the displacement speed of the head. Specifically, the control unit 50 calculates the head movement speed Vxf by differentiating the movement amount with respect to time based on the temporal transition of the head position Xf. Then, when the moving speed Vxf is equal to or less than a threshold value Δd that can be regarded as substantially zero, the change of the displacement direction of the head position is determined.

  According to this configuration, by determining the conversion based on the moving speed Vxf of the head, even when the sharpness near the time of conversion or near the minimum value is small in the movement trajectory of the occupant's head, the conversion is detected effectively. It becomes possible. In addition, it is possible to detect the change of the occupant head before the timing at which the occupant head changes.

  In this embodiment, it is preferable to determine that the point P2 shown in FIG. In the present embodiment using the head moving speed Vxf as a determination parameter, such a determination can also be easily performed.

  In the first and second embodiments, the example in which the airbag means that is the occupant protection means is an airbag unit attached to the side roof rail SR has been described. However, the airbag means in the present invention is not limited to this, and is, for example, a side air that is attached to a door, a seat, a body side, and the like and inflates and deploys between an occupant side portion and a vehicle body member (vehicle structure). It may be a bag. The airbag means includes a front airbag that is attached to a seat belt, a steering wheel, a dashboard, and the like and inflates and deploys between the front of the occupant and the vehicle body member (vehicle structure). Is restrained from being released from the vehicle by inertial force by inflating around the occupant and absorbing the inertial force of the occupant.

Explanatory drawing which shows the state of the vehicle to which the passenger | crew protection device concerning 1st Embodiment was applied, and the passenger | crew who rides the said vehicle Explanatory drawing schematically showing the configuration of the passenger protection device Explanatory drawing which shows the operation state of each support part 11-16 A perspective view schematically showing the rearview mirror 30 and the camera 33 Block configuration diagram of occupant protection device centering on control unit 50 The flowchart which shows a series of procedures of the passenger | crew protection process concerning 1st Embodiment. Illustration of rollover area and non-rollover area Flowchart showing a farside occupant protection processing routine Explanatory drawing showing the change of head position Flowchart showing near-side occupant protection processing routine Timing chart showing transition of head position Xf of occupant on far side Timing chart showing the transition of the head position Xn of the passenger on the near side Timing chart showing transition of head position Xf of occupant on far side Explanatory diagram showing the restraint state of the posture change of the occupant and the state of head behavior Explanatory drawing of the conversion judgment of the head position concerning 2nd Embodiment

Explanation of symbols

S ... Seat 11, 12 ... Lumber support part 13, 14 ... Rhino support part 15, 16 ... Knee support part 20 ... Seat belt mechanism 21 ... Retractor 22 ... Webbing 23 ... Shoulder anchor 24 ... Inner buckle 25 ... Tongue 30 ... Rearview mirror DESCRIPTION OF SYMBOLS 31 ... Mirror main body 32 ... Camera stay 33 ... Camera 40 ... Side airbag unit 41 ... Airbag main body 50 ... Control part 51 ... Sheet sensor 52 ... Roll rate sensor 53 ... Lateral acceleration sensor 55 ... Lumber support actuator 56 ... Cy support actuator 56 ... Knee support actuator 57 ... Knee support actuator 58 ... Air bag actuator 58 ... Belt actuator

Claims (7)

Position detecting means for detecting the position of the head of an occupant in the vehicle;
Occupant protection means for suppressing contact between the vehicle structure forming the occupant space and the occupant head;
Control means for operating the occupant protection means in response to a timing at which the change of the displacement direction of the occupant head is determined based on the transition of the head position detected by the position detection means. Crew protection device. Motion state detection means for detecting the motion state of the vehicle;
Based on the motion state of the vehicle detected by the motion state detection means, further comprising a prediction means for predicting inversion of the vehicle in advance,
The said control means operates the said passenger | crew protection means according to the timing when the overturn of the vehicle was predicted by the said prediction means, and the change of the displacement direction of the passenger | crew's head was determined. Occupant protection device. It further has a restraining means for restraining the posture change of the occupant,
The occupant protection device according to claim 2, wherein the control means operates the restraining means at a timing when the overturning of the vehicle is predicted by the prediction means.   The occupant protection device is configured by one or a combination of irreversible seat belt means for irreversibly restraining an occupant and airbag means for irreversibly deploying an airbag. The occupant protection device according to claim 1 or 2.   The restraint means includes a reversible seat belt means for reversibly restraining the occupant, a lumbar support means for reversibly restraining the lateral movement of the occupant's waist, and a reversible lateral movement of the occupant's thigh. Characterized in that it is composed of any one or a combination of a cy-support means for restraining the knee and a knee support means for reversibly restraining the lateral movement of the occupant's legs. The occupant protection device according to claim 3.   The control means returns the restraining means from the restrained state to the non-restrained state when it is determined that the vehicle is not overturned after the predicting means predicts the overturn of the vehicle. The occupant protection device according to claim 3 or 5.   The occupant protection device includes a occupant seated on a pair of seats arranged in a lateral direction of the vehicle, a occupant seated on a seat on a side where a wheel is lifted due to an increase in tilt of the vehicle during a rollover, and an occupant seated on the other seat The occupant protection device according to any one of claims 1 to 6, wherein the change of the displacement direction of the occupant head is determined independently.

Images