JP2015085761A - Occupant leg portion protection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent or suppress the twist of an occupant ankle while maintaining the constraint performance of both knee portions by a knee airbag.SOLUTION: In an occupant leg portion protection device 10, since a center region of a lower part of a knee airbag 16 in a vehicle width direction is not limited in expansion in a vehicle fore-and-aft direction by a tether, a shin airbag 18 integrally arranged at the region is expanded to a vehicle rear side, and gripped between both shin portions LT, RT. Since an expansion width of the shin airbag 18 in the vehicle width direction is set equal to a dimension between both the shin portions of an occupant P in the vehicle width direction, both the shin portions of the occupant P can be constrained by the knee airbag 16 without making the occupant P in a position with legs open. Furthermore, both the shin portions of the occupant P can be supported from the inside in a left-and-right direction by the shin airbag 18. As a result, a right foot RF of the occupant P can be prevented from carelessly falling to a brake pedal side from an accelerator pedal 24.

Description

  The present invention relates to an occupant leg protection device that protects an occupant's leg in a vehicle collision.

  In the occupant protection device described in Patent Document 1 below, when a vehicle collision occurs, the airbag of the posture correction means stored at the front end of the seat cushion is inflated and deployed between both knees of the seated occupant, Open both legs with the knees open outwards. Thereafter, the knee airbag of the shock absorbing means is inflated and deployed forward of both knee heads to receive both knee heads.

JP 2005-145381 A

  By the way, when the vehicle has an asymmetrical collision such as an oblique collision, the seated occupant moves inertially forward obliquely. For example, when the driver's seat side of the so-called left-hand drive vehicle has an asymmetrical collision, the seated occupant of the driver's seat moves inertially diagonally toward the vehicle front side and the vehicle width direction outside. In this case, the front end of the vehicle body floor may invade obliquely into the vehicle rear side and the vehicle width direction due to the collision load. As a result, it is assumed that the right foot of the seated occupant falls from the accelerator pedal toward the brake pedal and the right ankle is twisted. In this respect, in the occupant protection device as described above, since the seated occupant is in the open leg position before restraining both kneecaps by the knee airbag, it is considered that the above-described ankle twist can be prevented or suppressed. .

  However, when the seated occupant is in the open leg position, there is a possibility that both knees may collide with a door trim, a center console, or the like located on the side. In addition, since both knees are restrained by the knee airbag in an open leg position, the load from the waist that is about to move inertially forward of the vehicle acts to further expand the leg angle. It is conceivable that the knee is further pushed outward. Therefore, there is room for improvement from the viewpoint of maintaining the restraint performance of both knees by the knee airbag.

  In view of the above facts, the present invention has an object to provide an occupant leg protection device capable of preventing or suppressing the ankle of a seated occupant from being twisted while maintaining the restraint performance of both knees by a knee airbag. And

  The occupant leg protection device according to the first aspect of the present invention is a knee airbag that is provided in front of a vehicle seat and inflates and deploys in front of the vehicle at both knees of a seated occupant when gas is supplied therein. And is provided integrally or separately from the knee airbag, and is inflated and deployed to a position lower than both knees of the seated occupant by supplying gas therein, and is interposed between both shins of the seated occupant A tibial airbag in which an inflated width in the vehicle width direction is set to be equal to a dimension in the vehicle width direction between the two shin portions, and a gas generator that supplies gas into each airbag by being activated. ing.

  In the “integral” according to claim 1, when the knee airbag and the tibial airbag are formed of the same base fabric, the base fabric of the knee airbag and the base fabric of the tibial airbag are sewn. The case where it integrates by the above etc. is included. On the other hand, in the “separate body” according to claim 1, the knee airbag base fabric and the tibial airbag base fabric are not integrated by sewing or the like, and the knee airbag and the tibial airbag can be separated. Is formed.

  Further, in the first aspect, the dimension in the vehicle width direction between both shins of the seated occupant is, for example, an AM50 (50th percentile of an American adult male) dummy seated in a normal seating posture on a vehicle seat and the right foot Measured with accelerator pedal and left foot on footrest. Therefore, this vehicle width direction dimension changes with vehicles.

  Furthermore, the “equivalent” described in claim 1 does not have to be exactly the same. In other words, even if the inflated width of the shin airbag in the vehicle width direction is slightly larger than the dimension in the vehicle width direction between the shin portions of the seated occupant, the shin portions are separated from each other by the timber airbag inflated and deployed between the shin portions. It is only necessary to be set so as not to be spread in the direction. In addition, even when the inflated width of the tibial airbag in the vehicle width direction is slightly narrower than the dimension in the vehicle width direction between the both shin parts of the seated occupant, both shin parts of the seated occupant are supported from the inner side in the left-right direction by the tibi airbag. Anything that can do.

  In the first aspect of the present invention, for example, when the vehicle has a frontal collision, the gas generator is activated, and the gas from the gas generator is supplied to the knee airbag and the shin airbag. As a result, the knee airbag is inflated and deployed in front of the knees of the seated occupant, and the tibial airbag is inflated and deployed to a position lower than the knees of the seated occupant and is interposed between the shin parts. Since the inflated width in the vehicle width direction is set to be equal to the dimension in the vehicle width direction between the two shin parts, the knee airbag does not open the seated occupant and the knee airbag of the seated occupant The part can be restrained. Thereby, the restraint performance of both knee parts by a knee airbag can be maintained. Moreover, both shin portions of the seated occupant can be supported from the inside in the left-right direction by the shin airbag. As a result, for example, the right foot of the seated occupant can be prevented from inadvertently dropping from the accelerator pedal to the brake pedal side, so that the right heel of the seated occupant can be prevented or suppressed.

  An occupant leg protection device according to a second aspect of the present invention is the occupant leg protection device according to the first aspect of the present invention, wherein the knee airbag has an upper tether and a pair of left and right lowers for limiting the inflation of the knee airbag in the vehicle front-rear direction. A side tether is provided, and the portion between the pair of left and right lower tethers in the knee airbag is not restricted in the vehicle front-rear direction expansion. The shin airbag provided integrally is inflated toward the vehicle rear side.

  Note that the up / down / left / right directions described in claim 2 are directions when the knee airbag is inflated and deployed, and coincide with the up / down / left / right directions of the vehicle.

  In the invention according to claim 2, among the pair of upper and lower tethers that may be conventionally provided in the knee airbag, the lower tether is divided into left and right, thereby providing the tibial airbag integrally with the knee airbag. be able to. Thereby, the above-described effects can be obtained with a very simple configuration.

  An occupant leg protection device according to a third aspect of the present invention is the occupant leg protection device according to the first aspect, wherein the shin airbag is integrally provided at a lower portion of a bag body constituting the knee airbag. An upper tether that restricts expansion of the bag body in the vehicle front-rear direction is provided inside the portion constituting the knee airbag, and the bag is located inside the portion constituting the shin airbag in the bag body. A lower tether is provided to limit the expansion of the body in the vehicle width direction.

  In the invention according to claim 3, by providing the upper tether and the lower tether inside the bag body constituting the knee airbag, the tibial airbag is integrally provided at the lower part of the bag body. This shin airbag is restrained from expanding in the vehicle width direction by the lower tether and is interposed between both shin portions of the seated occupant. As a result, it is possible to increase the size of the tibial airbag interposed between the both shin parts while suppressing an increase in the capacity of the bag body including the shin airbag, so that both shin parts are favorably secured by the shin airbag. It becomes possible to support. As a result, the effect of preventing or suppressing the seated occupant from twisting the ankle can be improved.

  According to a fourth aspect of the present invention, there is provided the occupant leg protecting apparatus according to the first aspect, wherein the shin airbag is integrally provided at a lower portion of the bag body constituting the knee airbag, The shape of the base fabric is set such that the inflating width in the vehicle width direction of the portion constituting the shin airbag is smaller than the inflating width in the vehicle width direction of the portion constituting the knee airbag.

  In the invention according to claim 4, the shape of the base fabric of the bag body constituting the knee airbag is set as described above, so that the shin airbag is integrally provided at the lower portion of the bag body. Thereby, the effect which prevents or suppresses a seated passenger | crew twisting an ankle can be improved, suppressing the increase in the capacity | capacitance of a bag body similarly to the invention of Claim 3.

  An occupant leg protection device according to a fifth aspect of the present invention is the occupant leg protection device according to the first aspect, wherein the knee airbag and the shin airbag are separately formed and rolled in opposite directions in a common case. The gas generator is constituted by two inflators provided in the respective airbags.

  In the invention according to claim 5, when the knee airbag and the tibial airbag formed separately are inflated and deployed from inside the case, the airbags that are roll-folded in the opposite directions are separated from each other. Can be inflated and deployed. Thereby, the shin airbag can be inflated and deployed further downward to support the side close to both ankles in both shin portions of the seated occupant. As a result, the effect of preventing or suppressing the seated occupant from twisting the ankle can be improved. Further, since gas is supplied from separate inflators into the knee airbag and the shin airbag formed separately, the deployment timing and the internal pressure of each airbag can be changed.

  According to a sixth aspect of the present invention, in the occupant leg protection device according to the first aspect, in the first aspect, the knee airbag and the shin airbag are integrally formed with a base end portion in opposite directions to each other in a common case. The gas generator is a single inflator provided at the base end, and gas from the inflator is distributed into the airbags.

  In the invention according to claim 6, when the knee airbag and the tibial airbag, in which the base end portion is integrally formed, are inflated and deployed from within the case, the airbags that are roll-folded in opposite directions to each other, It can be inflated and deployed away from each other. Thereby, the shin airbag can be inflated and deployed further downward to support the side close to both ankles in both shin portions of the seated occupant. As a result, the effect of preventing or suppressing the seated occupant from twisting the ankle can be improved. Further, since the gas generated by one inflator is distributed in each airbag, the cost can be reduced compared to the case where two inflators are used.

  An occupant leg protection device according to a seventh aspect of the present invention is the occupant leg protection device according to the first aspect, wherein the shin airbag is formed separately from the knee airbag, and the front end portion of the seat cushion of the vehicle seat, Or it is arrange | positioned in the site | part ahead of the said vehicle seat in the vehicle body floor part, and the said gas generator is comprised by the two inflators each provided in each said airbag.

  In the invention according to claim 7, since the tibial airbag formed separately from the knee airbag is arranged as described above, the tibial airbag is inflated and deployed further downward to be seated. The side close to both ankles in both shin parts of the occupant can be supported. As a result, the effect of preventing or suppressing the seated occupant from twisting the ankle can be improved. Further, since gas is supplied from separate inflators into the knee airbag and the shin airbag formed separately, the deployment timing and the internal pressure of each airbag can be changed.

  As described above, in the occupant leg protection device according to the present invention, it is possible to prevent or suppress the ankle of the seated occupant from being twisted while maintaining the restraining performance of both knees by the knee airbag.

FIG. 5 is a partial cross-sectional view of a state in which the knee airbag and the shin airbag provided in the occupant leg protection device according to the first embodiment of the present invention are inflated and deployed, as viewed from the vehicle width direction outside, taken along line F1-F1 in FIG. It is a figure corresponding to the cut surface along. It is the rear view which looked at the expansion | deployment deployment state of the knee airbag with which the passenger | crew leg part protection apparatus is equipped, and the shin airbag from the vehicle rear side. It is the perspective view which looked at the expansion | deployment deployment state of the knee airbag and the shin airbag from the diagonally backward side of the vehicle. It is the fragmentary sectional view which looked at the state where both knee parts and both shin parts of a seated crew member were restrained by the knee airbag and the shin airbag from the vehicle rear side. (A) is sectional drawing which shows the cut surface along the F5A-F5A line of FIG. 4, (B) is sectional drawing which shows the cut surface along the F5B-F5B line of FIG. ) Is a cross-sectional view showing a cut surface along line F5C-F5C in FIG. 4, and (D) is a cross-sectional view showing a cut surface along line F5D-F5D in FIG. It is a top view which shows the condition of the left side of the compartment front part when the left side of the vehicle which concerns on a comparative example carries out the diagonal collision. It is the fragmentary sectional view which looked at the state where both knee parts of a seated crew member are restrained by the knee airbag carried in the vehicles concerning a comparative example from the vehicles back side. It is the fragmentary sectional view which looked at the state where both knee parts and both shin parts of a seated crew member are restrained by knee airbag and shin airbag concerning a 1st embodiment from the vehicles back side. It is the diagram which compared the relationship between the time after diagonal collision generate | occur | produced, and the twist angle of the right occupant of a seated passenger | crew by the comparative example and 1st Embodiment. It is a fragmentary sectional view corresponding to FIG. 1 which shows the modification of 1st Embodiment. It is the perspective view which looked at the expansion | deployment deployment state of the knee airbag and shin airbag provided with the passenger | crew leg part protection apparatus which concerns on 2nd Embodiment of this invention from the vehicle diagonally back side. It is the fragmentary sectional view which looked at the state where both knee parts and both shin parts of a seated crew member are restrained by the knee airbag and the shin airbag from the vehicle rear side. It is the rear view which looked at the expansion | deployment deployment state of the knee airbag and shin airbag provided with the passenger | crew leg part protection apparatus which concerns on 3rd Embodiment of this invention from the vehicle rear side. FIG. 14 is a partial cross-sectional view of the inflated and deployed state of the knee airbag and the tibial airbag as seen from the outside in the vehicle width direction, and (A) is a diagram corresponding to a cut surface along line F14A-F14A in FIG. (B) is a figure corresponding to the cut surface along the F14B-F14B line of FIG. It is the fragmentary sectional view corresponding to Drawing 1 which looked at the state where the knee airbag and tibial airbag with which the crew leg protection device concerning a 4th embodiment of the present invention was inflated and deployed were seen from the vehicle width direction outside. It is the top view which looked at the expansion | deployment deployment state of the knee airbag and the shin airbag from the vehicle upper side. (A) is sectional drawing which looked at the state before the inflation deployment of the knee airbag and the shin airbag from the vehicle width direction outer side, and (B) is the inflation deployment of the knee airbag and the shin airbag. It is sectional drawing which looked at the middle state from the vehicle width direction outer side. It is the fragmentary sectional view corresponding to Drawing 1 which looked at the state where the knee airbag and tibial airbag with which the crew leg protection device concerning a 5th embodiment of the present invention is inflated and deployed were seen from the vehicle width direction outside. (A) is sectional drawing which looked at the state before the inflation deployment of the knee airbag and the shin airbag from the vehicle width direction outer side, and (B) is the inflation deployment of the knee airbag and the shin airbag. It is sectional drawing which looked at the middle state from the vehicle width direction outer side. It is the fragmentary sectional view corresponding to FIG. 1 which looked at the state which the knee airbag and shin airbag provided with the passenger | crew leg protection apparatus concerning 6th Embodiment of this invention inflated and deployed from the vehicle width direction outer side. It is the top view which looked at the inflated deployment state of the shin airbag from the vehicle upper side. It is the fragmentary sectional view corresponding to Drawing 1 which looked at the state where the knee airbag and tibial airbag with which an occupant leg protection device concerning a 7th embodiment of the present invention is inflated and deployed were seen from the vehicle width direction outside. It is the top view which looked at the inflated deployment state of the shin airbag from the vehicle upper side.

<First Embodiment>
An occupant leg protection device 10 according to a first embodiment of the present invention will be described with reference to FIGS. In addition, the arrow FR, arrow UP, and arrow OUT that are appropriately described in each figure respectively indicate the front direction (traveling direction), the upward direction, and the outside in the vehicle width direction of the vehicle. Hereinafter, when simply using the front / rear, left / right, and up / down directions, unless otherwise specified, the front / rear direction of the vehicle, the left / right direction of the vehicle left / right direction (vehicle width direction), and the up / down direction of the vehicle up / down direction are indicated. To do.

(Constitution)
As shown in FIG. 1, the occupant leg protection device 10 according to the first embodiment is provided in front of the vehicle seat 12, and gas is supplied from an inflator 14 that is a gas generation device to the inside. A knee airbag 16 that is inflated and deployed is provided. The knee airbag 16 is integrally provided with a shin airbag 18.

  The vehicle seat 12 is a so-called left-hand drive driver's seat, and is disposed on the left side of the front part of the passenger compartment. In FIG. 1, 20 is a steering shaft, 22 is a lower panel of an instrument panel, 24 is an accelerator pedal, 26 is a vehicle body floor portion, and RL is an occupant P () on which a vehicle seat 12 is seated. The right leg of a seated crew member). The occupant P here is an AM50 (50th percentile of an American adult male) dummy, and is seated on the vehicle seat 12 in a normal sitting posture.

  As shown in FIGS. 2 and 3, the knee airbag 16 is configured by a bag body 28 formed by sewing one or a plurality of base fabrics into a substantially inverted trapezoidal bag shape. An inflator 14 formed in a substantially columnar shape is accommodated inside the knee airbag 16 in a state of being inserted inside a diffuser (not shown) formed in a cylindrical shape. The knee airbag 16 is normally folded by a predetermined folding method such as roll folding or bellows folding, and is stored in the module case 30 together with the inflator 14.

  The module case 30 is formed in a box shape with a metal material, for example, and is disposed below the steering shaft 20. The module case 30 is fixed to structural components (instrument reinforcement, floor brace, etc.) of the vehicle body via a bracket (not shown), and a rear end portion is opened to the vehicle rear side. The inflator 14 accommodated in the module case 30 is fixed to the bottom wall of the module case 30 with a part of the diffuser and the knee airbag 16 sandwiched therebetween.

  The inflator 14 is electrically connected to an ECU 32 mounted on the vehicle. The ECU 32 is electrically connected to a collision detection unit 34 that detects that the vehicle has collided with the front. The collision detection unit 34 includes, for example, a longitudinal acceleration sensor that detects acceleration in the longitudinal direction of the vehicle and a lateral acceleration sensor that detects acceleration in the lateral direction of the vehicle, and the control unit of the occupant leg protection device 10 together with the ECU 32. Is configured.

  The ECU 32 activates the inflator 14 when detecting that the vehicle has collided with the front based on the signal from the collision detection unit 34. This frontal collision includes not only full-wrapped frontal collisions (symmetrical collisions) but also offset collisions, oblique collisions, and minute lap collisions (all asymmetrical collisions). When a pre-crash sensor for predicting (predicting) a frontal collision is electrically connected to the ECU 32, the inflator 14 is activated when the ECU 32 predicts a frontal collision based on a signal from the pre-crash sensor. You may make it the structure made.

  When the inflator 14 is activated, the gas ejected from the gas ejection portion provided in the inflator 14 is rectified by the diffuser and supplied into the knee airbag 16. Accordingly, the knee airbag 16 is inflated and deployed from the rear end opening of the module case 30 along the lower panel 22 to the vehicle rear side (vehicle seat 12 side) and the vehicle upper side. During the inflation and deployment, an airbag door (not shown) provided on the lower panel 22 of the instrument panel is opened by the inflation pressure of the knee airbag 16.

  As shown in FIGS. 1 and 4, the upper part of the inflated knee airbag 16 comes into contact with the left and right knees LN and RN of the occupant P from the front. In FIG. 4, LL is the left leg of the occupant P. In addition, the front, rear, left, right, and up and down directions of the knee airbag 16 described in the following description indicate directions when the knee airbag 16 is inflated and deployed unless otherwise specified. It almost coincides with the direction.

  Inside the knee airbag 16, an upper tether 36 and a pair of left and right lower tethers 38L, 38R are provided. The upper tether 36 is disposed in the upper portion of the knee airbag 16 and is sewn on the front and rear inner surfaces of the knee airbag 16 to partition the upper portion of the knee airbag 16 vertically. However, the upper tether 36 does not reach the left and right ends of the knee airbag 16, and gas flow paths 42 and 46 are formed between the upper tether 36 and the left and right ends of the knee airbag 16, respectively. Has been.

  The pair of left and right lower tethers 38 </ b> L and 38 </ b> R are provided to be separated from each other on the left and right ends of the lower portion in the knee airbag 16. The left lower tether 38L is located below the left end of the upper tether 36, and the right lower tether 38R is located below the right end of the upper tether 36. These lower tethers 38L and 38R are sewn on the front and rear inner surfaces of the knee airbag 16 in the same manner as the upper tether 36. Gas flow paths 48 and 50 are formed between the lower tethers 38L and 38R and the left and right ends of the knee airbag 16, respectively. A gas flow path 52 having a cross-sectional area wider than that of the gas flow paths 42, 46, 48, 50 is formed between the left and right lower tethers 38L, 38R.

  As shown in FIGS. 1 and 5A to 5C, the upper tether 36 has the same height as the left and right knees LN and RN of the occupant P in the inflated and deployed state of the knee airbag 16. It is provided so that it may be located in. On the other hand, as shown in FIGS. 5 (A) and 5 (B), the left and right lower tethers 38L and 38R of the left and right shin portions LT and RT of the occupant P are in the inflated and deployed state of the knee airbag 16. It is provided to be located at the same height as the upper end. The knee airbag 16 provided with the upper tether 36 and the lower tethers 38L and 38R is limited in expansion in the front-rear direction by these tethers, and as a whole expands in a flat pillow shape in the front-rear direction.

  However, as shown in FIG. 1 and FIG. 5 (D), the center region in the left-right direction in the lower portion of the knee airbag 16, that is, the region in which each of the tethers is not provided is not limited in the front-rear direction, and the vehicle It bulges backward. This region is a tibial airbag 18 (tibial airbag portion). The shin airbag 18 is constituted by a part of a bag body 28 constituting the knee airbag 16 and is integrated with the knee airbag 16. The shin airbag 18 is inflated and deployed to a position lower than the knee portions LN and RN of the occupant P, and is interposed between the left and right shin portions LT and RT of the occupant P (enters from the front side of the vehicle).

  In other words, in the present embodiment, the shin airbag 18 integrally provided at the lower portion of the knee airbag 16 is deployed so as to be sandwiched between the both shin portions LT and RT, and the both shin portions LT and RT are disposed inward in the left-right direction. It is configured to support from. In the inflated and deployed state, the shin airbag 18 has a lower end below the center of gravity of each of the right leg RL and the left leg LL that are lower limbs of the occupant P (refer to the center of gravity of the lower leg: the center of gravity G of the right leg RL shown in FIG. The shape is set so that the part is located. Thus, the center of gravity of the right leg RL and the left leg LL is supported by the shin airbag 18 from the inner side in the left-right direction. In FIG. 1, the center of gravity G is shown in front of the cross section of the shin airbag 18 for convenience of explanation.

  In the present embodiment, as shown in FIG. 5D, the inflated width L1 of the shin airbag 18 in the vehicle width direction is equal to the distance between the left and right lower tethers 38L, 38R. The expansion width L1 is set to be equal to (slightly wider here) the vehicle width direction dimension L2 between the both shin portions LT and RT. Specifically, the occupant P places the right foot RF on the accelerator pedal 24 (see FIG. 1) and the shin airbag 18 separates the shin portions LT and RT from each other with the left foot LF placed on the footrest (not shown). The expansion width L1 is set so as not to spread in the direction (outward in the left-right direction). In the present embodiment, the above-described expansion width L1 is set to be the same as the shortest distance between the left and right contact points between the bag body 28 and the both shin portions LT and RT. The right foot RF is a portion of the right leg RL below the right ankle RA, and the left foot LF is a portion of the left leg LL. It is the part below the left ankle LA.

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

  In the occupant leg protection device 10 having the above-described configuration, when the ECU 32 detects a frontal collision based on a signal from the collision detection unit 34, the inflator 14 is activated by the ECU 32 to configure the knee airbag 16 and the shin airbag 18. Gas is supplied into the bag body 28. Thereby, the knee airbag 16 is inflated and deployed in front of the knees LN and RN of the occupant P, and the tibial airbag 18 is inflated and deployed to a position lower than the knees LN and RN of the occupant P. It is interposed between the shin LT and RT.

  Since the inflated width L1 in the vehicle width direction is set to be equal to the vehicle width direction dimension L2 between the both shin portions LT and RT, the tibial airbag 18 does not have the occupant P in the open leg position, and the knee airbag 18 Accordingly, both knee portions LN and RN of the occupant P can be restrained. Thereby, the restraint performance of both knee parts LN and RN by the knee airbag 16 can be maintained. Moreover, the shin airbag 18 can support the shin parts LT and RT of the occupant P from the inner side in the left-right direction (inside the body). As a result, it is possible to prevent the right foot RF of the occupant P from inadvertently dropping from the accelerator pedal 24 toward the brake pedal, so that the right ankle RA of the occupant P can be prevented or suppressed from being twisted.

  The above effect will be described in detail using a comparative example 200 shown in FIGS. FIG. 6 is a plan view showing a situation on the left side of the front part of the passenger compartment when the left side of the vehicle according to the comparative example 200 has an oblique collision (so-called oblique collision). FIG. 7 is a partial cross-sectional view of a state in which the left and right knee portions LT and RT of the occupant P are restrained by the knee airbag 16 ′ mounted on the vehicle according to the comparative example 200 as seen from the vehicle rear side. Is shown. In the comparative example 200, the lower tether 38 of the knee airbag 16 ′ is not divided into right and left like the present embodiment, and is set from the left end side to the right end side of the knee airbag 16 like the upper tether 36. Yes. For this reason, the knee airbag 16 'is not provided with the shin airbag 18.

  As shown in FIG. 6, when the left side of the vehicle collides diagonally, the occupant P seated on the vehicle seat 12, which is the driver seat of the left-hand drive vehicle, tilts diagonally toward the vehicle front side and the vehicle width direction outside. Inertial movement (see arrow A in FIG. 6). Further, at this time, the front end portion of the vehicle body floor portion 26 obliquely enters the vehicle rear side and the vehicle width direction inner side due to the impact of the oblique collision (see arrow B in FIG. 6). As a result, the right foot RF of the occupant P falls from the accelerator pedal 24 to the brake pedal (not shown) (the collision side: here, the left side), and the right ankle RA of the occupant P is twisted as shown in FIG. It is done. In FIG. 7, θ is a twist angle of the right ankle RA.

  On the other hand, in the present embodiment, the right shin part RT of the occupant P can be supported from the left side by the shin airbag 18, so that the right foot RF can be prevented from falling off as described above. As a result, as shown in FIG. 8, the twist angle θ of the right ankle RA can be reduced as compared with the comparative example 200.

  FIG. 9 is a diagram showing the relationship between the time after the occurrence of the oblique collision and the twist angle θ of the right ankle RA. In FIG. 9, the time change of the twist angle θ of the right ankle in the present embodiment is indicated by a solid line, and the time change of the twist angle θ of the right ankle RA in the comparative example 200 is indicated by a dotted line. As shown in FIG. 9, in this embodiment, the twist angle θ of the right ankle RA toward the minus side (vehicle width direction outer side) is reduced by about 20 degrees compared to the comparative example 200 (arrow in FIG. 9). D). Thereby, the right ankle RA can be well protected.

  In the present embodiment, the center of gravity of the right leg RL and the left leg LL of the occupant P (see the center of gravity G of the right leg RL shown in FIG. 1) is supported from the inner side in the left-right direction by the tibial airbag 18. Displacement of the RL and the left leg LL inward in the left-right direction can be effectively suppressed. In addition, in this embodiment, since the occupant P is not placed in the open leg posture by the shin airbag 18, the left and right knees LN, RN are prevented from inadvertently colliding with the door trim, center console, and the like located on the side thereof. be able to.

  Further, in the present embodiment, of the pair of upper and lower tethers 36, 38 provided in the conventional knee airbag 16 '(see Comparative Example 200), the lower tether 38 is replaced with the left and right lower tethers 38L, 38R. It is divided. Thereby, the shin airbag 18 is provided integrally with the knee airbag 16. Therefore, the effects as described above can be obtained with a very simple configuration. In the present embodiment, the areas of the left and right lower tethers 38L and 38R are smaller than the area of the lower tether 38 of the conventional knee airbag 16 ', and the area between the left and right lower tethers 38L and 38R is smaller. A gas flow path 52 is formed in the bottom. As a result, the gas from the inflator 14 can be quickly supplied to the upper portion of the knee airbag 16 (bag body 28), so that the knee airbag 16 can be quickly moved forward of the knees LN and RN of the occupant P. Can be inflated and deployed.

  Further, in the present embodiment, the expansion width L1 in the vehicle width direction of the shin airbag 18 is set to be equal to the vehicle width direction dimension L2 between the both shin portions LT and RT, and the shin airbag 18 Inflate and deploy so as to be sandwiched between the parts LT and RT. Thereby, since both knee parts LN and RN can be prevented from being pushed from the front by the shin airbag 18, the cruciate ligaments of both knee parts LN and RN can be protected.

(Supplementary explanation of the first embodiment)
Note that, as in the modification shown in FIG. 10, the bag body 28 may be enlarged as compared to the first embodiment, and the module case 30 may be disposed below the first embodiment. Thereby, a lower position than the center of gravity of each of the right leg RL and the left leg LL (refer to the center of gravity G of the right leg RL shown in FIG. 1) can be supported, thereby improving the effect of reducing the ankle twist angle. Can be made. In this case, in order not to delay the inflation and deployment of the knee airbag 16 in front of the knee portions LN and RN, it is preferable to advance the sensing time of the frontal collision by the collision detection unit 34.

  Moreover, although the said 1st Embodiment demonstrated the case where the twist of the right ankle RA was prevented or suppressed by the shin airbag 18, the twist of the left ankle LA can also be prevented or suppressed by the shin airbag 18. That is, since both shin portions LT and RT are supported by the shin airbag 18 from the inner side in the left-right direction, the left foot LF can be prevented from inadvertently dropping from the footrest to the brake pedal side due to the impact of the right side oblique collision. As a result, the left ankle LA can be prevented or suppressed from being twisted.

  Moreover, although the said 1st Embodiment demonstrated the case where the leg parts RL and LL of the passenger | crew P who were seated on the vehicle seat 12 which is a driver seat of a left-hand drive vehicle were protected, this invention is not limited to this, It is also possible to protect the occupant's legs seated in the driver's seat of the steering wheel vehicle.

  Next, another embodiment of the present invention will be described. In addition, about the structure and effect | action similar to the said 1st Embodiment, the same code | symbol as the said 1st Embodiment is provided, and the description is abbreviate | omitted.

<Second Embodiment>
In FIG. 11, the inflated and deployed states of the knee airbag 62 and the shin airbag 64 provided in the occupant leg protecting device 60 according to the second embodiment of the present invention are shown in a perspective view as seen from the obliquely rear side of the vehicle. Yes. FIG. 12 is a partial cross-sectional view of the state in which the knees LN and RN and the shins LT and RT of the occupant P are restrained by the knee airbag 62 and the shin airbag 64 as viewed from the vehicle rear side. Is shown.

  In this embodiment, the shin airbag 64 is integrally provided at the lower portion of the bag body 68 constituting the knee airbag 62. An upper tether 70 that restricts the expansion of the bag body 68 in the vehicle front-rear direction is provided inside a portion (upper part) of the bag body 68 that constitutes the knee airbag 62. In addition, a lower tether 72 that restricts the expansion of the bag body 68 in the vehicle width direction is provided inside the portion of the bag body 68 that constitutes the tibial airbag 64.

  A plurality of communication ports 74 (openings: holes) are formed in the upper tether 70 and the lower tether 72, respectively. The gas ejected from the inflator 14 provided at the lower end of the shin airbag 64 is supplied to the upper portion of the bag body 68 through the plurality of communication ports 74. Thereby, the bag body 68, that is, the knee airbag 62 and the shin airbag 64 are inflated and deployed in a substantially T shape when viewed from the vehicle rear side.

  The inflated and deployed knee airbag 62 comes into contact with both knees LN and RN of the occupant P from the front. Further, the shin airbag 64 is inflated and deployed at a position lower than the knee portions LN and RN, and is interposed (pinched) between the shin portions LT and RT. The expansion width L1 of the shin airbag 64 is set to be equal to the vehicle width direction dimension L2 (see FIG. 5D) between the both shin portions LT and RT, as in the first embodiment. The inflated width L1 is the maximum width in the vehicle width direction of the inflated and deployed tibial airbag 64.

  In this embodiment, the configuration other than the above is the same as that of the first embodiment. Therefore, there are basically the same effects as the first embodiment. Moreover, in this embodiment, the upper tether 70 and the lower tether 72 are provided inside the bag body 68 constituting the knee airbag 62, so that the shin airbag 64 is integrally provided at the lower portion of the bag body 68. ing. The shin airbag 64 is restrained from expanding in the vehicle width direction by the lower tether 72 and is interposed between the shin portions LT and RT of the occupant P. Thereby, the magnitude | size of the shin airbag 64 interposed between both shin parts LT and RT can be expanded, suppressing the increase in the capacity | capacitance of the bag body 68 containing the shin airbag 64. FIG. As a result, it is possible to favorably support the swelled portion of the shin portions LT and RT inward in the left-right direction by the shin airbag 64, so that the effect of preventing or suppressing the occupant P from twisting the ankle (ankle twisting) Angle reduction rate) can be improved.

  Moreover, in the present embodiment, since the plurality of communication ports 74 are formed in the upper and lower tethers 70 and 72, it is preferable from the viewpoint of rapidly inflating and deploying the knee airbag 62 forward of the knee portions LN and RN. . Moreover, since the above-described effect can be obtained only by changing the shape of the base fabric of the bag body 68 and the upper and lower tethers 70 and 72, it is also preferable from the viewpoint of reducing the manufacturing cost. Furthermore, since both shin parts LT and RT are not pushed from the front, it is also suitable from the viewpoint of protecting the cruciate ligament of the occupant P.

<Third Embodiment>
FIG. 13 is a rear view of the knee airbag 82 and the shin airbag 84 provided in the occupant leg protection device 80 according to the third embodiment of the present invention as seen from the vehicle rear side. . This embodiment has a configuration close to that of the first embodiment, but, like the second embodiment, a tibial airbag 84 is integrally provided at a lower portion of a bag body 86 constituting the knee airbag 82. ing. In this embodiment, the lower tethers 38L and 38R according to the first embodiment are omitted.

  In the bag body 86, the inflating width L1 in the vehicle width direction of the part (lower part) constituting the shin airbag 84 is smaller than the inflating width L3 in the car width direction of the part (upper part) constituting the knee airbag 82. The shape of the base fabric is set so as to be. That is, the shape of the base fabric is set so that the bag body 86 is inflated and deployed in a substantially T shape when viewed from the vehicle rear side. In a state in which the bag body 86 is inflated and deployed, the knee airbag 82 faces the knees LN and RN of the occupant P from the front (see FIG. 14A), and the shin airbag 84 has both the shin parts LT. , RT (see FIG. 14B). The expansion width L1 of the shin airbag 64 is set to be equal to the vehicle width direction dimension L2 (see FIG. 5D) between the both shin portions LT and RT, as in the first embodiment.

  Also in this embodiment, the same operational effects as those of the second embodiment can be obtained. Moreover, it is only necessary to change the shape of the base fabric in the conventional knee airbag, which is preferable from the viewpoint of reducing the manufacturing cost.

<Fourth Embodiment>
FIG. 15 is a partial cross-sectional view corresponding to FIG. 1 in which the inflated and deployed states of the knee airbag 92 and the shin airbag 94 provided in the occupant leg protection device 90 according to the fourth embodiment of the present invention are viewed from the outside in the vehicle width direction. It is shown in the figure. FIG. 16 is a plan view of the inflated and deployed states of the knee airbag 92 and the shin airbag 94 as viewed from above the vehicle. In this embodiment, unlike the above embodiments, the knee airbag 92 and the shin airbag 94 are formed separately. In this embodiment, two inflators 96 and 98 are provided in the knee airbag 92 and the shin airbag 94, respectively. These inflators 96 and 98 constitute a gas generator.

  The knee airbag 92 is a well-known general one, and is inflated and deployed forward of the knees LN and RN of the occupant P by the pressure of gas ejected from the inflator 96 (shown in FIGS. 15 and 16). State). A tether 100 that restricts inflation of the knee airbag 92 in the front-rear direction is provided inside the bag body constituting the knee airbag 92.

  On the other hand, the tibial airbag 94 is constituted by a bag body that expands and deploys in a substantially spherical shape by the pressure of gas ejected from the inflator 98. The shin airbag 94 is inflated and deployed to a position lower than the knees LN and RN of the occupant P, and is interposed (pinched) between the shins LT and RT. The expansion width in the vehicle width direction of the shin airbag 94 is set to be equal to the vehicle width direction dimension between the both shin portions LT and RT, as in the above embodiments.

  As shown in FIG. 17A, the knee airbag 92 and the shin airbag 94 described above are normally housed by being folded in opposite directions in the module case 102 which is a common case. . The knee airbag 92 and the shin airbag 94 are fixed to the bottom wall of the module case 102 via inflators 96 and 98, respectively. The module case 102 is disposed below a steering shaft (not shown), and is fixed to vehicle body components (instrument reinforcement, floor brace, etc.) via a bracket (not shown). The rear end portion of the module case 102 opens toward the vehicle rear side, and faces the airbag door 104 provided on the lower panel 22 of the instrument panel.

  The inflators 96 and 98 are electrically connected to the ECU 32 (not shown in FIGS. 15 to 17), and are activated when the ECU 32 detects a frontal collision. When the inflators 96 and 98 are activated, the knee airbag 92 and the shin airbag 94 are inflated and deployed by the pressure of the gas ejected from the inflators 96 and 98 (see FIG. 17B). At this time, the tear line set in the airbag door 104 is broken and the airbag door 104 is opened. Further, when the knee airbag 92 and the tibial airbag 94 are unfolded by this inflation and deployment, the airbags 92 and 94 are folded so that the airbags 92 and 94 are inflated and deployed in opposite directions. The winding direction is set. Accordingly, as shown in FIG. 15, the knee airbag 92 is inflated and deployed obliquely upward toward the rear of the vehicle, and comes into contact with both knees LN and RN of the occupant P from the front. Further, the shin airbag 94 is inflated and deployed toward the vehicle rear obliquely downward, and is sandwiched between the both shin portions LT and RT of the occupant P.

  In this embodiment, the shin airbag 94 can be inflated and deployed further downward to support the side of the occupant P near the both ankles RA and LA in the shin parts LT and RT. Thereby, the reduction rate of an ankle twist angle can be made high. Further, gas is supplied from separate inflators 96 and 98 into the knee airbag 92 and the tibial airbag 94 formed separately, so that the deployment timing and internal pressure of each airbag 92 and 94 can be changed. Can do. Furthermore, since the above-described effect can be obtained without lowering the position of the inflator 96 for the knee airbag 92, it is possible to prevent the inflation and deployment of the knee airbag 16 ahead of the knee portions LN and RN. .

<Fifth Embodiment>
FIG. 18 is a partial cross-sectional view of the inflated and deployed state of the knee airbag 92 and the shin airbag 94 provided in the occupant leg protecting apparatus 110 according to the fifth embodiment of the present invention as seen from the outside in the vehicle width direction. ing. The knee airbag 92 and the tibial airbag 94 in this embodiment are normally rolled and housed in opposite directions in the common module case 102 as in the fourth embodiment (FIG. 19). (See (A)). The knee airbag 92 and the shin airbag 94 are formed in the same shape as the knee airbag 92 and the shin airbag 94 according to the fourth embodiment, but the base end portion is formed integrally. . In FIGS. 18, 19 (A), and 19 (B), reference numeral 112 denotes a sewing portion that sews the proximal end portion of the knee airbag 92 and the proximal end portion of the tibial airbag 94.

  The proximal end portion of the knee airbag 92 and the proximal end portion of the shin airbag 94 are communicated with each other. This communication part is provided with one inflator 14 that constitutes a gas generator. When the inflator 14 is activated, gas is supplied (distributed) into the airbags 92 and 94, and the airbags 92 and 94 are inflated and deployed as in the fourth embodiment. Also in this embodiment, similarly to the fourth embodiment, the reduction rate of the ankle twist angle can be increased. In addition, in this embodiment, since the gas generated by one inflator 14 is distributed into the airbags 92 and 94, the cost can be reduced as compared with the case where two inflators are used.

<Sixth Embodiment>
FIG. 20 is a partial cross-sectional view corresponding to FIG. 1 in which the inflated and deployed states of the knee airbag 122 and the shin airbag 124 included in the occupant leg protecting device 120 according to the sixth embodiment of the present invention are viewed from the outside in the vehicle width direction. It is shown in the figure. FIG. 21 shows a plan view of the inflated and deployed state of the shin airbag 124 as seen from above the vehicle. In this embodiment, the knee airbag 122 and the shin airbag 124 are formed separately.

  The knee airbag 122 is configured to be similar to the knee airbag 16 in the first embodiment. However, in the knee airbag 122, the lower tether 38 is not divided into right and left like the first embodiment, and is set from the left end side to the right end side of the knee airbag 122 like the upper tether 36. Yes. This knee airbag 122 is inflated and deployed in front of both knees LN and RN of the occupant P upon receiving gas supply from the inflator 14 (not shown in FIGS. 20 and 21) as in the first embodiment. .

  On the other hand, the shin airbag 124 is formed of a long bag body, is folded in a predetermined folding manner, and is housed in the module case 128 together with the inflator 126. The module case 128 is fixed to the front end portion of the seat cushion 12A, and the front end portion is open. The inflator 126 constitutes a gas generator together with the inflator 14, and is activated when the ECU 32 detects a frontal collision. Thereby, the gas from the inflator 126 is supplied into the shin airbag 124, and the shin airbag 124 is inflated and deployed toward the front side of the vehicle. The inflated and deployed tibial airbag 124 is inflated and deployed to a position lower than the knees LN and RN of the occupant P, and is interposed (pinched) between the both shins LT and RT. The inflating width of the shin airbag 124 in the vehicle width direction is set to be equal to the dimension in the vehicle width direction between the both shin portions LT and RT, as in the above embodiments.

  In this embodiment, since the tibial airbag 124 formed separately from the knee airbag 122 is disposed as described above, the tibial airbag 124 is inflated and deployed further downward, and the occupant P The sides near both ankles LA and RA in both shin portions LN and RN can be supported. As a result, the reduction rate of the ankle twist angle can be increased. In addition, since gas is supplied from the separate inflators 14 and 126 into the knee airbag 122 and the shin airbag 124 formed separately, the deployment timing and the internal pressure of the airbags 122 and 124 can be changed. Can do.

<Seventh Embodiment>
FIG. 22 is a partial cross-sectional view corresponding to FIG. 1 in which the inflated and deployed states of the knee airbag 122 and the shin airbag 124 included in the occupant leg protecting device 130 according to the seventh embodiment of the present invention are viewed from the outside in the vehicle width direction. It is shown in the figure. FIG. 23 shows a plan view of the inflated and deployed state of the shin airbag 124 as seen from above the vehicle. In this embodiment, the configuration is similar to that of the sixth embodiment, but the module case 128 that houses the tibial airbag 124 is disposed in a portion of the vehicle body floor portion 26 that is closer to the vehicle front side than the vehicle seat 12. ing. This embodiment also has basically the same functions and effects as those of the sixth embodiment. Moreover, in this embodiment, since the shin airbag 124 is disposed at a position closer to both shin portions LN and RN than in the sixth embodiment, the capacity of the shin airbag 124 is smaller than that in the sixth embodiment. can do.

  The present invention has been described above with reference to several embodiments. However, the present invention is not limited to the configurations of the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. It goes without saying that the scope of rights of the present invention is not limited to the above embodiments.

10 Crew Leg Protection Device 12 Vehicle Seat 12A Seat Cushion 14 Inflator (Gas Generator)
16 knee airbag 18 tibi airbag 26 vehicle body floor 36 upper tether 38 lower tether 60 occupant leg protection device 62 knee airbag 64 tibi airbag 68 bag body 70 upper tether 72 lower tether 80 occupant leg protection device 82 Knee airbag 84 tibi airbag 86 bag body 90 occupant leg protection device 92 knee airbag 94 tibi airbag 96, 98 inflator (gas generator)
102 Module case (common case)
110 Crew Leg Protection Device 120 Crew Leg Protection Device 122 Knee Airbag 124 Tibial Airbag 126 Inflator (Gas Generator)
130 occupant leg protection device P seated occupant LN, RN seated occupant knee LT, RT seated occupant's shin L1 inflated width of shin bag L2 vehicle width direction dimension between both shins

Claims (7)

A knee airbag provided in front of the vehicle seat and inflated and deployed in front of the vehicle at both knees of a seated occupant by supplying gas therein;
The knee airbag is integrated with or separated from the knee airbag, and is inflated and deployed to a position lower than both knees of the seated occupant by supplying gas therein. A tibial airbag in which an inflated width in the width direction is set to be equal to a dimension in the vehicle width direction between the both shin parts;
A gas generator for supplying gas into each airbag by being activated;
An occupant leg protection device.   In the knee airbag, an upper tether and a pair of left and right lower tethers that restrict expansion of the knee airbag in the vehicle front-rear direction are provided, and the pair of left and right lower tethers in the knee airbag is provided. 2. The tibial airbag integrally provided in the vehicle width direction central region at the lower part of the knee airbag is inflated toward the rear side of the vehicle because the portion between the two is not restricted in the vehicle longitudinal direction. The occupant leg protection device described.   The tibial airbag is integrally provided at a lower portion of a bag body that constitutes the knee airbag, and a portion of the bag body that constitutes the knee airbag is disposed in a vehicle longitudinal direction of the bag body. 2. An upper tether that restricts inflation is provided, and a lower tether that restricts inflation of the bag in the vehicle width direction is provided inside a portion of the bag that constitutes the tibial airbag. The occupant leg protection device described in 1.   The tibial airbag is integrally provided at a lower portion of a bag body constituting the knee airbag, and the bag body has an inflated width in a vehicle width direction of a portion constituting the tibial airbag. The occupant leg protection device according to claim 1, wherein a shape of the base fabric is set so as to be smaller than an expansion width in a vehicle width direction of a portion constituting the bag.   The knee airbag and the shin airbag are separately formed and housed in rolls folded in opposite directions in a common case, and the gas generators are respectively stored in the airbags. The occupant leg protection device according to claim 1, wherein the occupant leg protection device is configured by two inflators provided.   The knee airbag and the shin airbag are integrally formed with a base end portion and housed in a common case by being folded in opposite directions, and the gas generator includes the base end portion. The occupant leg protection device according to claim 1, wherein a gas from the inflator is distributed into the airbags.   The tibial airbag is formed separately from the knee airbag, and is disposed at a front end portion of a seat cushion of the vehicle seat or a portion of the vehicle floor that is on the vehicle front side of the vehicle seat. The occupant leg protection device according to claim 1, wherein the gas generator is configured by two inflators respectively provided in the airbags.

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