JP6555162B2 - Crew protection device - Google Patents

Description

  The present invention relates to an occupant protection device.

  In Patent Document 1, when the upper part of the occupant sinks into the seat back at the time of the rear collision of the vehicle, the center part of the seat back facing the occupant's upper back moves backward with respect to the left and right side parts. A vehicle seat in which the upper body of an occupant sufficiently sinks into a seat back is disclosed.

JP 2012-136055 A

  In the technique described in Patent Document 1, the center portion of the seat back is moved backward by inertia applied to the occupant at the time of a vehicle rear collision.

  However, there is room for improvement in order to protect the seated person more effectively in the actual collision state of the vehicle and the relationship with the restraint device (seat belt or the like).

  In view of the above facts, an object of the present invention is to improve the protection performance of a seated person in an occupant protection device.

  In a first aspect, a seat skeleton member that forms a skeleton of a vehicle seat, a seat back plate that is provided in a seat back of the vehicle seat and is fixed to the seat skeleton member, and supports a load of a seated person, and a vehicle A collision prediction device that predicts a collision of the vehicle, and a constraint that restrains the seat occupant on the vehicle seat and applies a pressing force to the seat back on the seat occupant before the collision based on a collision prediction by the collision prediction device A member and a release device for releasing the fixation of the seat back plate to the seat frame member based on the collision prediction.

  In this occupant protection device, when the collision prediction device does not predict a vehicle collision, the seat back plate is fixed to the seat frame member and can reliably support the load of the seated person. Further, the restraining member restrains the seated person on the vehicle seat.

  When the collision prediction device predicts a vehicle collision, the restraining member applies a force for pressing the seated person toward the vehicle seat before the collision based on the prediction. Further, the release device releases the fixation of the seat back plate to the seat frame member. Since the seat occupant moves to the vehicle seat side by the force from the restraint member acting on the seat occupant, the seat occupant can be restrained more reliably by the restraint member, and the seat occupant's protection performance is improved.

  Since the present invention is configured as described above, in the occupant protection device, the protection performance of the seated person at the time of collision can be improved.

FIG. 1 is a perspective view showing an occupant protection device of a reference example . FIG. 2 is a side view showing an occupant protection device of a reference example . FIG. 3 is an enlarged cross-sectional view of the occupant protection device of the reference example in the vicinity of the lock mechanism. FIG. 4 is an enlarged cross-sectional view of the occupant protection device of the reference example in the vicinity of the lock mechanism. FIG. 5 is a block diagram of an occupant protection device of a reference example . FIG. 6 is a flowchart showing a control flow in the occupant protection device of the reference example . FIG. 7 is a schematic diagram illustrating an example of a spring mass model that reproduces the front collision phenomenon of a vehicle. FIG. 8 is a graph showing an example of the relationship between the amount of vehicle movement and the deceleration in the front collision phenomenon of the vehicle. FIG. 9A is a graph showing the relationship between the time and deceleration at the time of the frontal collision of the vehicle, and FIG. 9B shows the relationship between the movement amount (stroke) of the seated person and the deceleration at the time of the frontal collision of the vehicle. It is a graph to show. FIG. 10 is a graph showing the relationship between time and speed at the time of frontal collision of the vehicle. FIG. 11 is a graph showing the relationship between the vehicle initial speed and the seated person maximum deceleration at the time of a frontal collision of the vehicle. FIG. 12 is a plan view partially showing the occupant protection device of the first embodiment . FIG. 13 is a plan view partially showing the occupant protection device of the first embodiment . FIG. 13 is a graph qualitatively showing the spring characteristics of the support spring in the occupant protection device of the first embodiment .

Hereinafter, an occupant protection device 12 of a reference example will be described with reference to the drawings. In each drawing, the vehicle width direction is indicated by an arrow W, the vehicle front is indicated by an arrow F, and the vehicle upper direction is indicated by an arrow U, as appropriate. In the state shown in FIGS. 1 and 2, the vehicle width direction matches the seat width direction, the vehicle front matches the seat front, and the vehicle information matches the seat upper.

As shown in FIGS. 1 and 2, the occupant protection device 12 of the reference example includes a vehicle seat 14 and a seat belt device 16. The seat belt device 16 is an example of a restraining device in the present invention.

  The vehicle seat 14 includes a seat cushion 18 installed on a floor panel of an automobile, and a seat back 20 erected from the rear side of the seat cushion 18. A rotation shaft 22 extending in the seat width direction is provided on the rear side of the seat cushion 18. The seat back 20 can take a reclining posture or a forward leaning posture by rotating around the rotation shaft 22.

  A seat back frame 24 is disposed in the seat back 20. The seat back frame 24 is an example of a seat frame member. The seat back frame 24 maintains the outer shape of the seat back 20.

  A seat cushion frame 26 is disposed in the seat cushion 18. The outer shape of the seat cushion 18 is maintained by the seat cushion frame 26, and in particular, the load on the seated person can be reliably supported. A cushion material having a predetermined shape is disposed around the seat back frame 24 and the seat cushion frame 26, and the outer side of the cushion material 28 is covered with a skin material.

  As shown in detail in FIG. 2, the seat belt device 16 includes a webbing 32 and a pretensioner 34 that is provided on the vehicle body and holds both ends of the webbing 32. The pretensioner 34 normally holds the webbing 32 so that it can be wound and unwound. However, when the pretensioner 34 is driven, the webbing 32 is wound up. A force in the direction toward the seat back 20 is applied to the seated person SP wearing the webbing 32 due to the winding of the webbing 32.

  As shown in FIG. 2, a seat back plate 36 is disposed in the seat back 20. As shown in FIGS. 3 and 4, the seat back frame 24 is provided with a lock mechanism 38.

  In the normal state, as shown in FIG. 3, the lock pin 40 of the lock mechanism 38 is inserted into the lock hole 44 of the seat back plate 36 under the urging force of the lock spring 42, and the movement of the seat back plate 36 is Locked.

  On the other hand, when the gas generator 46 of the lock mechanism 38 is operated and gas is ejected, the lock pin 40 resists the urging force of the lock spring 42 in the direction of the arrow M1 due to the gas pressure, as shown in FIG. Move and exit from the lock hole 44. In this state, the seat back plate 36 is unlocked, and the seat back plate 36 can move in the vehicle front-rear direction with respect to the seat back frame 24. The lock mechanism 38 is a device for releasing the fixation (locking) of the seat back plate 36 to the seat back frame 24 as described above, and is an example of a release device in the present invention.

  As shown in FIG. 5, the vehicle includes a distance sensor 50 that detects the distance to the collision target, a speed sensor 52 that detects a relative speed with respect to the collision target, and an image recognition sensor 54 that recognizes the collision target. Is provided. The image recognition sensor 54 may be a camera that captures a collision target. In this case, the image recognition may be performed by the control device 48. As will be described later, based on the input data from the distance sensor 50 and the speed sensor 52, the control device 48 predicts the collision of the vehicle with the collision object, which is the collision prediction device in the present invention.

  Data detected by these sensors is sent to the control device 48. The control device 48 controls the operation of the pretensioner 34 and the gas generator 46 based on these detection data.

Next, the operation of the reference example will be described.

  In the normal state, as shown in FIG. 3, the lock pin 40 of the lock mechanism 38 is inserted into the lock hole 44. For this reason, the seat back plate 36 is locked to the seat back frame 24 and cannot move. For this reason, the seat back plate 36 can reliably support the load used by the seated person.

In the occupant protection device 12 of this reference example , the control device 48 drives and controls the pretensioner 34 and the gas generator 46 based on the flow shown in FIG.

  First, in step S <b> 102, the control device 48 obtains the distance L to the collision target based on the input data from the distance sensor 50. In step S104, the control device 48 obtains a relative speed v with respect to the collision target based on the input data from the speed sensor 52. Note that the temporal relationship between step S102 and step S104 is not limited and may be reversed or substantially simultaneous.

  In step S106, the control device 48 calculates a predicted collision time t to the collision target object from the distance L and the relative speed v. t = L / v.

  In the control device 48, an operation threshold time T is set in advance. The operation threshold time is a time that is a criterion for determining whether or not to operate the pretensioner 34 and the gas generator 46 in comparison with the predicted collision time t calculated in step S106.

  In step S108, the controller 48 determines whether or not the predicted collision time t is equal to or shorter than the operation threshold time T. If the predicted collision time t exceeds the operation threshold time T, the process returns to step S102. The occupant protection device 12 is maintained in a normal state.

  When it is determined that the predicted collision time t is equal to or shorter than the operation threshold time T, the process proceeds to step S110. In step S110, the image of the collision target is recognized based on the input data from the image recognition sensor 54.

  In step S <b> 112, it is determined whether or not the collision target is an operation target in the occupant protection device 12. The operation target is an object that serves as a determination index when determining whether to operate the gas generator 46 and the pretensioner 34. For example, if the collision target is a vehicle such as an automobile or a fixed structure such as a building or a utility pole, it corresponds to the operation target.

  If it is determined in step S112 that the collision target does not correspond to the operation target, the process returns to step S102. The occupant protection device 12 is maintained in a normal state.

  In step S112, when it is determined that the collision target corresponds to the operation target, the control device 48 proceeds to step S114. In step S114, the control device 48 activates (ignites) the gas generator 46, and further activates the pretensioner 34 in step S116. Note that the temporal relationship between the driving of the gas generator 46 and the driving of the pretensioner 34 is not limited, and may be the reverse of the above or may be substantially simultaneous.

  As a result, before the vehicle collides with the collision object, the lock pin 40 comes out of the lock hole 44 and the seat back plate 36 is unlocked as shown in FIG. . Furthermore, since the pretensioner 34 winds up the webbing 32, the tightening force of the pretensioner 34 acts on the seat back plate 36 via the seat occupant SP. Then, the seated person and the seat back plate 36 move toward the vehicle rear side with respect to the seat back frame 24.

In the occupant protection device 12 of the reference example, the occupant of the vehicle seat 14 is moved rearward with respect to the vehicle before the vehicle collides with the collision target. Thereby, the protection performance with respect to the seated person at the time of a vehicle front collision is improving.

  This point will be described in more detail below.

First, the vehicle model 102 shown in FIG. 7 is introduced. The vehicle model 102 is a spring mass model that reproduces the front collision phenomenon of the vehicle. In this vehicle model 102, an initial gap between the seated person SP and a vehicle structural member (for example, a steering wheel) on the front side is defined as L ₁ (gap in a normal state). In order to reliably protect the seated person, the allowable stroke to the front side based on the vehicle is set to L ₁ +50 mm (for example, column stroke allowance). The restraint spring characteristic in the vehicle model 102 is a linear characteristic, and the rigidity is changed to correspond to various conditions. The initial speed V ₀ of the vehicle model 102 was 55 km / h. That is, collides with the initial speed _V 0 = 55km / h vehicle model 102 object struck MC of, but seated person SP moves forward side with respect to the vehicle model 102, as the upper limit _{L 2} of the moving amount _L 1 + 50 mm Set.

  FIG. 8 shows the relationship between the amount of movement of the vehicle floor and the deceleration on the basis of the collision position with the collision object in the vehicle model 102. As shown in the range (A) of the graph, the vehicle model 102 decelerates to a predetermined position after the collision and the deceleration becomes maximum, and then slightly returns to the rear side as shown in the range (B). .

Here, the passenger protection device 12 of the present reference example will be described in comparison with the passenger protection device of the first comparative example. As described above, the occupant protection device 12 of the present reference example is configured to predict a collision with the collision exercised article and operate the pretensioner 34 and the gas generator 46 before the collision. In the following, as an example, the pretensioner 34 and the gas generator 46 are operated about 30 msec before the collision.

  On the other hand, in the occupant protection device of the first comparative example, the pretensioner 34 is operated about 10 msec after the collision.

FIG. 9A shows simulation results of the time and the deceleration of the seated person's body with respect to the time of the collision in the occupant protection devices of the reference example and the first comparative example. FIG. 9B shows simulation results of the seat occupant's stroke (position with respect to the vehicle) and the seat occupant's body deceleration based on the collision position in the occupant protection devices of the reference example and the first comparative example. Has been. In each graph, the solid line indicates a reference example , and the alternate long and short dash line indicates a first comparative example. In addition, the dashed-two dotted line in each graph respond | corresponds to the 2nd comparative example mentioned later.

As shown by the alternate long and short dash line in FIG. 9 (A), in the occupant protection device of the first comparative example, the restraint is started on the occupant state after about 10 msec of the collision. The deceleration is maximum at around 100 msec. Further, as shown by the one-dot chain line in FIG. 9B, in the occupant protection device of the first comparative example, the occupant protection is performed so that the deceleration becomes the maximum value when the movement amount of the seated person reaches L ₂ mm. The characteristics of the device were adjusted.

On the other hand, as shown by a solid line in FIG. 9A, in the occupant protection device of the reference example , the deceleration acts on the occupant upper body from about 30 msec before the collision. This is because the upper body of the seated person is moved to the rear side of the seat by operating the gas generator 46 and the pretensioner 34 about 30 msec before the collision. The deceleration becomes maximum when the time from the collision exceeds 100 msec.

As shown by the solid line in FIG. 9 (B), in the occupant protection device of the reference example, as the deceleration when the amount of movement of the occupant reaches L ₂ is the maximum value, to adjust the characteristics of the occupant protection device However, this deceleration is significantly lower than the occupant protection device of the first comparative example. As described above, the upper limit of the amount of movement in the front of the seated person at the time of collision is assumed L _2. In this case, if the gas generator 46 and the pretensioner 34 are operated at a predetermined timing before the collision as in the occupant protection device of this reference example , the maximum deceleration (load) that acts on the upper body of the seated person. Can be reduced.

FIG. 10 shows changes in speed with respect to the upper body of the seated person and the road surface of the vehicle in the occupant protection devices of the reference example and the first comparative example with respect to the time of the collision. In this graph, the solid line indicates the upper body of the seated person in the reference example , the alternate long and short dash line indicates the upper body of the seated person in the first comparative example, and the broken line indicates the vehicle (same in the reference example and the first comparative example). .

In the case of the first comparative example, after the collision, the seated person tries to move forward with inertia with respect to the vehicle, so that the speed of the seated person is higher than the speed of the vehicle. Then, at a certain time T ₀ after the collision (in the example of FIG. 10, at a time slightly exceeding 100 msec from the collision), the speed of the seated person becomes equal to the speed of the vehicle (the relative speed becomes zero), Restraint ends. In the first comparative example, the speed change ΔV ₀ of the occupant upper body from the state where the relative speed before the collision is zero to the end of restraint is large.

On the other hand, in the case of this reference example , before the collision (specifically, about 30 msec), the restraint of the seated person is started by the operation of the gas generator 46 and the pretensioner 34. After the restraint, the seated person first decelerates, and then the vehicle decelerates (after the collision). However, since the deceleration of the vehicle is larger, at a certain time T ₁ after the collision (in the example of FIG. After 30 msec), the relative speed temporarily becomes zero. At this time, the rearward displacement of the seated person based on the vehicle is maximized.

Thereafter, the speed of the vehicle becomes lower than the speed of the seated person, the relative speed becomes zero at a certain time T ₂ after collision (about 120 msec in the example of FIG. 10), and the restraint is finished. Therefore, in the reference example , the speed change ΔV ₁ of the upper body of the seated person from the state where the relative speed is temporarily zero after the collision until the end of the restraint is smaller than the speed change ΔV ₀ in the first comparative example. Actually, since the kinetic energy of the seated person is proportional to the square of the speed (speed), the effect of reducing the kinetic energy of the seated person in this reference example is exhibited by the square of the speed ratio appearing in FIG. The

Thus, in the occupant protection device of this reference example , before the vehicle collides with the collision target, the gas generator 46 and the pretensioner 34 are actuated to restrain the seated person and move the seat rearward. Thereby, the speed change after the rearward displacement of the seated person reaches the maximum is reduced, and the protection performance for the seated person at the time of the collision is improved.

For example, it may be possible to adopt a configuration in which the seat back plate 36 is slowly moved to the vehicle rear side before the collision using an actuator or the like and the pretensioner 34 is operated after the collision. 9 (A) and 9 (B) shows an example indicated by a two-dot chain line, as a second comparative example, the seat back plate 36 is retracted to the same extent as the maximum retraction amount of this reference example before the collision, and the collision is about 10 msec. This is a case where the pretensioner is driven later.

From FIG. 9A, in the second comparative example, as in the first comparative example, the deceleration becomes the maximum value after about 100 msec after the collision, and the value is slightly smaller than that in the first comparative example. small. As can be seen from FIG. 9 (B), the deceleration acting upon the amount of movement of the upper body of the seated person reaches L ₂ is smaller than the first comparative example, greater than the reference example. That is, in the second comparative example, the effect of protecting the seated person by reducing the deceleration acting on the seated person after the vehicle collision is smaller than that of the reference example .

11, similarly to the above vehicle model 102 (see FIG. 7), the upper limit of the forward movement amount allowed seated person during a vehicle collision and L _2, the spring constant of the restraining spring for each initial speed of the vehicle The maximum deceleration acting on the occupant when optimized is shown in relation to the initial speed of the vehicle. In FIG. 11, the solid line corresponds to the reference example , and the alternate long and short dash line corresponds to the first comparative example.

From this graph, the reference example, in the entire region of the assumed speed range (from 50 km / h to 65km / h), than the first comparative example, it is seen that lower maximum deceleration acting on the vehicle occupant. For example, the maximum deceleration, the initial speed of the vehicle to realize a deceleration _{G 1} occurring at 55km / h in the first comparative example is about 67km / h in Reference Example.

Thus, in the occupant protection device 12 of the reference example , even when the initial speed of the vehicle is high, the deceleration acting on the seated person after the collision can be kept low. That is, the vehicle speed corresponding to the protection of the seated person and the protection of the seated person by the occupant protection device 12 can be achieved at a high level. For example, while maintaining the characteristics of the pretensioner 34 (restraint device), it is possible to deal with a collision at a higher speed and a seated person with a high weight.

  Furthermore, by changing the characteristics of the pretensioner 34 (restraint device) according to the weight of the seated person and the collision speed of the vehicle, the seated person can be more effectively protected during a vehicle collision according to various conditions. Can be realized. The weight of the seated person can be detected, for example, by providing a weight sensor on the vehicle seat 14. As the collision speed, data detected by the speed sensor 52 described above can be used, and further, data relating to a collision target detected by the image recognition sensor 54 can be used in combination. Alternatively, the age of the seated person may be registered in the control device 48 in advance, and the characteristics of the pretensioner 34 (restraint device) may be changed according to the age.

Next, a first embodiment will be described. In the first embodiment , the same elements and members as those in the reference example are denoted by the same reference numerals as those in the reference example, and detailed description thereof is omitted. Moreover, in 1st embodiment , since the external appearance shape of a vehicle seat is the same as that of a reference example , illustration is abbreviate | omitted.

As shown in FIG. 12, in the occupant protection device 212 of the first embodiment, a seat back plate 236 for a vehicle seat is attached to a seat back frame 224 by a link mechanism 238.

  The link mechanism 238 has two links 238L that intersect in a substantially “X” shape when the vehicle seat is viewed from above. As can be seen from the comparison between FIGS. 12 and 13, the seat back plate 236 can move to the vehicle rear side while the two links 238 </ b> L change the crossing angle.

A pair of left and right support springs 242 are arranged between the seat back plate 236 and the seat back skeleton member (may be the seat back frame 224 or another seat back skeleton member). The support spring 242 has a spring characteristic shown in FIG. That is, until the compression length reaches a threshold value L ₁ is roughly proportional to the compression length S and the spring force F, the compression length S reaches a threshold value L _1, as shown in FIG. 13, the longitudinal direction of the intermediate portion Bends (so-called buckling occurs).

  When the support spring 242 is bent in this manner, the spring force becomes weaker than that before the bending. When the restraining force of the pretensioner 34 (see FIG. 2) acts on the seat back plate 236 via the seated person, the movement of the seat back plate 236 toward the seat rear side is allowed. That is, when the support spring 242 is buckled, the movement of the seat back plate 236 toward the vehicle rear side is unlocked.

The threshold L ₁ is the normal state (pretensioner 34 (see FIG. 2) is not operating) state, the compression length L ₂ when the load from the seated person upper body (normal weight) is applied Is also set longer. Accordingly, in the normal state, the support spring 242 does not buckle.

Also in the occupant protection device 212 of the first embodiment having such a configuration, as in the case of the occupant protection device 12 of the reference example , the pretensioner 34 is operated before the collision with the collision target object, thereby Is moved to the rear side of the seat. Thereby, the protection performance with respect to the seated person at the time of a vehicle front collision is improving.

As can be seen from the above description, when the vehicle is predicted to collide with the collision target, the release device of the present invention releases the fixation (lock) of the seat back plate to the seat back frame based on the prediction result. For example, the specific configuration is not limited. For example, in the reference example , the lock pin 40 may be extracted from the lock hole 44 by an actuator using a solenoid or the like.

In the first embodiment , the seat back plate substantially includes the support spring 242 having the spring characteristics shown in FIG. 14, and effectively uses the restraining force of the pretensioner operated based on the above-described prediction result. Release the lock. That is, it can be said that the release member includes the pretensioner 34 and the support spring 242.

12 occupant protection device 14 vehicle seat 16 seat belt device (an example of restraint member)
24 Seat back frame (an example of a seat frame member)
26 Seat cushion frame 32 Webbing 34 Pretensioner 36 Seat back plate 38 Lock mechanism (an example of a release device)
40 lock pin 48 control device (an example of a collision prediction device)

Claims (1)

A seat skeleton member forming a skeleton of a vehicle seat;
A seat back plate supporting the load of the sitting person provided to the seat back of the vehicle seat,
A collision prediction device for predicting a vehicle collision;
A restraining member that restrains the seat occupant to the vehicle seat and applies a pressing force against the seat back to the seat occupant before the collision based on a collision prediction by the collision prediction device;
When the compression length is equal to or less than a predetermined value, the seat back plate is supported by the seat frame member by a spring force, and when the compression length exceeds a predetermined value, the seat back plate moves to the rear side of the seat. An allowable support spring;
An occupant protection device.

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