JP2011051549A - Airbag device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an airbag device capable of protecting the upper body and the knees of an occupant while reducing a gas amount. <P>SOLUTION: The airbag device 10 for a front passenger seat includes a main bag 26 that is developed to restrain the upper body U of the occupant P, a subbag 28 that is developed to restrain the knees K of the occupant P, a high pressure expansion portion 40 that is developed in the subbag 28, a gas supply flow passage portion 38 to develop the high pressure expansion portion 40 by an internal pressure higher than that of the subbag 28, and a gas discharge-restraining means 42 (check valve) as a structure for giving the internal pressure difference. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an airbag apparatus including a first bag that restrains an upper body of an occupant and a second bag that restrains a knee.

  An airbag device is known in which an airbag for restraining a knee is connected to an airbag for restraining the upper body of an occupant (for example, see Patent Document 1). There is also known an airbag device that simultaneously inflates and deploys an airbag for restraining the upper body of an occupant and an airbag for restraining a knee by gas supply from a common pressure accumulator (for example, Patent Document 2).

Japanese Utility Model Publication No.7-17662 JP-A-51-23917

  By the way, when integrating the airbag for restraining the knee with the airbag for restraining the upper body, an inflator having a capacity equivalent to the sum of the capacities of the two inflators for inflating and deploying these independently is required. The Rukoto.

  An object of the present invention is to obtain an airbag device capable of protecting the upper body and knees of an occupant while reducing the amount of gas.

  The airbag device according to the first aspect of the present invention includes a first bag that restrains an upper body of a vehicle occupant from the front side in the vehicle front-rear direction by being inflated and deployed upon receiving gas supply, and the first bag. The second bag that restrains the occupant's knee from the front side in the vehicle front-rear direction by receiving a gas supply from the folded state and being expanded and deployed, and a smaller capacity than the second bag, A third bag that is inflated and deployed in the second bag upon receiving a gas supply from a folded state, an inflator that generates gas supplied to the first bag, the second bag, and the third bag, at least the An internal pressure difference providing structure for making the internal pressure of the third bag higher than the internal pressure of the second bag when the second bag restrains the knee of the vehicle occupant.

  In the airbag device according to the first aspect, for example, when a gas is supplied from the inflator during a frontal collision of the vehicle, the first to third bags are inflated and deployed by the gas. Then, a 1st bag restrains a passenger | crew's upper body and a 2nd bag restrains a passenger | crew's knee. During the restraint, the third bag inflated and deployed in the second bag is maintained at a higher internal pressure than the second airbag by the internal pressure difference providing structure. For this reason, in this airbag apparatus, while a passenger | crew's knee is restrained softly by the 2nd bag, the reaction force accompanying this restraint is supported by the 3rd bag (via a vehicle body via a relatively high internal pressure).

  Here, in this airbag apparatus, since the internal pressure difference is set in the second and third bags that protect the occupant's knee, in other words, the entire bag that restrains the knee is not at high pressure, so the knee is restrained. The amount of gas for ensuring equivalent knee protection performance can be reduced as compared with a configuration in which the entire bag is at a high pressure.

  Thus, in the airbag device according to the first aspect, the upper body and knees of the occupant can be protected while reducing the gas amount.

  An airbag apparatus according to a second aspect of the present invention is the airbag apparatus according to the first aspect, wherein the second bag is configured to be inflated and deployed on the rear side in the vehicle front-rear direction with respect to the instrument panel. The third bag is configured to be inflated and deployed on the instrument panel side in the second bag.

  In the airbag device according to claim 2, the second airbag is inflated and deployed between the instrument panel and the occupant's knee, and the third bag is closer to the instrument panel than the knee in the second bag. Inflated and deployed in a biased state. As a result, the occupant's knee is restrained softly first, and after the consumption of the cushioning stroke of the second bag alone, the knee is restrained by the third bag having a relatively high internal pressure to prevent the knee from interfering with the instrument panel. Or it can be suppressed.

  An airbag apparatus according to a third aspect of the present invention is the airbag apparatus according to the second aspect, wherein the internal pressure difference providing structure includes a gas supply path for directly supplying the gas from the inflator to the third bag. And a gas discharge suppressing means for suppressing discharge of gas from the third bag when the internal pressure of the third bag exceeds a predetermined value.

  In the airbag device according to claim 3, when the gas from the inflator is supplied to the third bag through the gas supply path and the internal pressure of the third bag exceeds a predetermined value, the gas discharge suppressing means causes the gas from the third bag to be discharged. Gas emission is suppressed. Thereby, in this airbag apparatus, the internal pressure of a 3rd bag is maintained in the relatively high state. The small-capacity third bag is inflated and deployed to high pressure in a short time from the operation of the inflator by supplying the gas from the inflator directly through the gas supply path, thereby effectively protecting the occupant's knees. Contribute to.

  The airbag device according to a fourth aspect of the present invention is the airbag device according to any one of the first to third aspects, wherein the third bag has a width that can restrain both knees of the occupant. It is a single bag.

  In the airbag device according to the fourth aspect, the third bag is configured as a single bag having a width that covers both knees of the occupant. For this reason, it is possible to expand and deploy the first to third bags by gas supply with a simple structure (gas supply path or the like).

  An airbag apparatus according to a fifth aspect of the present invention is the airbag apparatus according to any one of the first to third aspects, wherein the third bag can individually restrain both knees of the occupant. A pair of left and right are provided.

  In the airbag device according to claim 5, a pair of left and right third bags are provided corresponding to the left and right knees of the occupant. For this reason, this airbag apparatus contributes to the further reduction of gas amount.

  As described above, the airbag device according to the present invention has an excellent effect of being able to protect the upper body and knees of the occupant while reducing the amount of gas.

It is a sectional side view which shows the deployment state of the airbag in the airbag apparatus which concerns on the 1st Embodiment of this invention. It is a back sectional view showing typically the airbag which constitutes the airbag apparatus concerning a 1st embodiment of the present invention. It is a sectional side view which shows the deployment state of the airbag in the airbag apparatus which concerns on the 2nd Embodiment of this invention. It is a back sectional view showing typically an airbag which constitutes an airbag device concerning a 2nd embodiment of the present invention.

  A passenger seat airbag apparatus 10 as an airbag apparatus according to a first embodiment of the present invention will be described with reference to FIGS. In addition, arrow FR, arrow UP, and arrow W appropriately described in each figure respectively indicate the vehicle V to which the passenger seat airbag device 10 is applied, the vehicle front direction (traveling direction), the upward direction, and the vehicle width direction of the passenger seat 12. Is shown. Further, in the following description, when the shape of the airbag 20 (its constituent part) is described, the shape in the inflated and deployed state is referred to unless otherwise specified.

  FIG. 1 is a schematic side cross-sectional view of a front portion in a passenger compartment C of an automobile V in an operating state of a passenger seat airbag device 10. As shown in this figure, a passenger seat 12 as a vehicle seat is disposed in the front part of the passenger compartment C. The passenger seat 12 includes a seat cushion 12A for the occupant P to sit forward and a seat back 12B that supports the seated occupant P of the seat cushion 12A from the rear of the vehicle.

  A windshield glass 14 that defines the front end of the vehicle in the passenger compartment C is disposed in front of the passenger seat 12. An instrument panel 16 is provided below the vehicle with respect to the windshield glass 14. An upper portion 16A of the instrument panel 16 in the vehicle vertical direction protrudes toward the passenger seat 12, and a seated occupant P of the passenger seat 12 puts his feet under the upper portion 16A. Therefore, the seated occupant P of the passenger seat 12 is configured to bring its knee K close to the upper portion 16 </ b> A of the instrument panel 16.

  The passenger seat airbag apparatus 10 includes an airbag module 18 disposed in the instrument panel 16. The airbag module 18 includes an airbag 20 described later, an inflator 22 for supplying gas to the airbag 20, and an airbag case 24 holding (partially containing) the airbag 20 and the inflator 22. It is configured. The airbag module 18 is held by an attachment portion 16 </ b> B provided on the instrument panel 16 in the airbag case 24.

  In this embodiment, as shown in FIG. 1, the airbag 20 includes a main bag 26 as a first bag for protecting the upper body U of the seated occupant P, and a sub bag 28 as a second bag for protecting the knee K. And have. For this reason, in the passenger airbag device 10, the airbag module 18 is provided in the vicinity of the rearmost portion of the vehicle in the upper portion 16 </ b> A of the instrument panel 16 so as to face the vehicle rearward and upward. Specifically, in the airbag device 10 for the passenger seat, the airbag case 24 of the airbag module 18 is held by the mounting portion 16B of the instrument panel 16 in a posture that opens toward the rear of the vehicle and upward of the vehicle. Yes.

  The airbag case 24 holds (partially accommodates) the airbag 20 in a folded state as shown by a two-dot chain line in FIG. The airbag 20 is kept in a folded state by being wrapped in a holding sheet or the like (not shown). The inflator 22 is fixedly held by the airbag case 24 in a state in which a part including the gas ejection port 22 </ b> A is inserted into the airbag 20. In this embodiment, the inflator 22 is a so-called disk-type inflator, and a sufficient gas capacity is ensured for the airbag 20 having the main bag 26 and the subbag 28 as described above.

  The main bag 26 of the airbag 20 is inflated and deployed between the windshield glass 14 and the instrument panel 16 and the upper body U of the seated occupant P, and restrains the relative movement of the upper body U forward of the vehicle. It has become. In this embodiment, a vent hole 25 for adjusting internal pressure is formed in the main bag 26. The sub bag 28 is inflated and deployed between the instrument panel 16 (upper part 16A) and the knee K, and restrains the relative movement of the knee K forward of the vehicle. The main bag 26 and the sub bag 28 of the airbag 20 are integrally configured as shown in FIG.

  Specifically, the main bag 26 is formed so as to be inflated and deployed in a bag shape by a base cloth 30 that constitutes an upper portion and an intermediate portion of the airbag 20 in the vehicle vertical direction. In this embodiment, the main bag 26 is a so-called twin chamber structure airbag in which left and right bags adjacent in the vehicle width direction are connected as shown in FIG. The main bag 26 is formed such that the rear ends of the left and right bags (chambers) restrain the left and right shoulders (or the vicinity thereof) of the seated occupant P, respectively.

  The sub bag 28 is formed in a bag shape that opens upward in the vehicle with the base cloth 32, and the opening edge is joined to the vehicle lower opening edge of the main bag 26 by sewing or the like. Thereby, the airbag 20 has comprised the big bag shape as a whole. The base fabric 32 is different from the base fabric 30 in that the surface is subjected to a texture seal process such as a silicon coat, and prevents gas leakage from the main bag 26 via the texture (suppresses the base fabric 30). ). The silicon coat for holding the internal pressure of the sub bag 28 is preferably applied to the inner surface of the sub bag 28 from the viewpoint of preventing gas leakage. Note that a tether or the like (not shown) for regulating the expansion of the sub bag 28 in the vehicle front-rear direction may be provided in the airbag 20 that is deployed in a large bag shape as a whole.

  The airbag 20 constituting the passenger seat airbag apparatus 10 includes an inner tube 34 as a flexible gas flow path member that guides the gas of the inflator 22 to the main bag 26 and the subbag 28. The inner tube 34 is opened by a base cloth 35, which is a woven fabric similar to the base cloth 30, independent of the main bag 26 and the sub bag 28, in front of the vehicle and downward of the vehicle as shown in FIG. It is configured as a bag body that is inflated and deployed in a substantially “U” shape. Specifically, the inner tube 34 extends from the airbag case 24 that opens toward the rear of the vehicle and toward the upper side of the vehicle as described above, and is deployed so as to be folded back toward the front of the vehicle and the lower side of the vehicle. It is set as the structure.

  Although not shown, the inner tube 34 is folded together with the main bag 26 and the sub bag 28 in the main bag 26 and the sub bag 28 so as to be inflated and deployed in the main bag 26 and the sub bag 28 as a whole. It is. An intermediate portion of the inner tube 34 is partitioned by a tether 36 as a partition wall.

  A portion of the inner tube 34 that is deployed on the inflator 22 side with respect to the tether 36 is a gas supply passage portion 38 as a gas supply passage, and a portion of the inner tube 34 that is on the tip side from the tether 36 is a high-pressure deployment as a third bag. Part 40. The tether 36 is formed with a communication hole 36 </ b> A through which the gas of the inflator 22 flows from the gas supply flow path portion 38 to the high pressure deployment portion 40. In addition, the gas supply flow path portion 38 is provided with a communication portion 38 </ b> A that allows the gas of the inflator 22 to flow into the main bag 26 and the subbag 28.

  As shown in FIG. 1, the high-pressure deploying portion 40 is deployed in a substantially rectangular shape that is long in the vehicle width direction in the rear view as shown in FIG. It is like that. The length along the vehicle width direction of the high-pressure deployment part 40 is set so as to support both knees K of the occupant P (see the imaginary line in FIG. 2).

  In the passenger airbag device 10, a check valve (one-way valve) 42 is formed around the communication hole 36 </ b> A in the tether 36 as a gas discharge suppression means. The check valve 42 has a cloth piece 42 </ b> A that covers the communication hole 36 </ b> A from the inside of the high-pressure deployment part 40 (outside the gas supply flow path part 38), and the high pressure deployment part through the communication hole 36 </ b> A from the gas supply flow path part 38. The gas supply to 40 is allowed. On the other hand, the check valve 42 is configured such that when the internal pressure (dynamic pressure) of the high-pressure deployment part 40 becomes higher than the internal pressure of the gas supply flow path part 38, the cloth piece 42A closes the communication hole 36A by the internal pressure. .

  On the other hand, a high-pressure part preferential deployment structure 44 is provided in the communication part 38 </ b> A of the gas supply flow path part 38. The high-pressure portion preferential deployment structure 44 is mainly configured by a tear seam 46 in which the peripheral portion of the communication portion 38A in the gas supply flow path portion 38 of the inner tube 34 is closed by sewing. The tear seam 46 is broken when the internal pressure of the inner tube 34 exceeds a predetermined value, and opens the communication portion 38A. As a result, the passenger seat airbag apparatus 10 is configured such that the gas supply start timing to the main bag 26 and the sub bag 28 is delayed with respect to the gas supply start timing to the inner tube 34 including the high-pressure deployment part 40. ing. 2 shows a state in which the communication portion 38A is closed by the tear seam 46 in order to facilitate understanding of the configuration of the high-pressure portion preferential deployment structure 44.

  Therefore, in the passenger seat airbag device 10, the sub-bag 28 is covered so as to cover the high-pressure deployment part 40 after the high-pressure deployment part 40 is inflated and started to be deployed (which can also be regarded as the start of deployment of a part of the sub-bag 28). The expansion and the expansion of the main bag 26 are started, and the expansion and the expansion of the main bag 26 are started. In the passenger airbag device 10, the knee bag 50 that protects the knee K of the occupant P is configured by the subbag 28 and the high-pressure deployment portion 40 that is deployed inside the subbag 28. .

  As shown in FIG. 1, the knee airbag 50 is configured such that the high-pressure deployment part 40 is deployed on the instrument panel 16 side (vehicle front side) in the sub-bag 28. Accordingly, the knee airbag 50 is configured such that at least the front side in the vehicle front-rear direction is a high pressure portion and the rear side is a low pressure portion in a range in the vehicle width direction in which the high pressure deployment portion 40 is provided.

  In the passenger airbag device 10 described above, the gas supply flow path portion 38 that supplies the gas of the inflator 22 directly to the high-pressure deployment portion 40 and the check valve 42 that suppresses gas discharge from the high-pressure deployment portion 40. These correspond to the internal pressure difference providing structure in the present invention. In addition to these, the high-pressure part preferential deployment structure 44 for preferentially supplying the high-pressure development part 40 may be considered to correspond to the internal pressure difference providing structure in the present invention. In the passenger airbag device 10, a pair of left and right communication portions 38A are provided so as to supply gas toward both sides in the vehicle width direction by breaking the tear seam 46, respectively.

  Further, as shown in FIG. 1, an airbag door 48 that is broken and opened by the inflation and deployment pressure of the airbag 20 is formed at a portion of the instrument panel 16 to which the airbag module 18 is attached. The airbag door 48 according to this embodiment is opened up and down around the hinge portion when the instrument panel 16 is cleaved at a groove-like tear line formed on the inner surface thereof, and the instrument panel 16 has an opening. It comes to form. Through this opening, the airbag 20 is allowed to be inflated and deployed outside the instrument panel 16, that is, in the passenger compartment C.

  In the passenger-side airbag device 10 described above, for example, when a frontal collision of the vehicle V is detected or predicted to be unavoidable based on an output of a collision sensor (not shown), an airbag as a control device (not shown) is used. The ECU operates the inflator 22.

  Next, the operation of this embodiment will be described.

  In the passenger airbag device 10 configured as described above, when a frontal collision of the automobile V is detected or predicted based on a signal from the collision sensor, the airbag ECU activates (ignites) the inflator 22. Then, the airbag 20 that has received the gas supply from the inflator 22 is inflated in the instrument panel 16 and inflated and deployed in the vehicle compartment C through an opening formed by deploying the airbag door 48 with the deployment pressure.

  At this time, the high-pressure deployment part 40 to which gas is supplied from the inflator 22 through the gas supply flow path part 38 is first inflated and deployed. When the internal pressure of the high-pressure deployment unit 40 exceeds the internal pressure of the gas supply flow path unit 38, the check valve 42 closes the communication hole 36A, and gas discharge from the high-pressure deployment unit 40 is suppressed. As a result, the high-pressure deployment part 40 is maintained in a high internal pressure state.

  On the other hand, when the internal pressure of the gas supply flow path portion 38 exceeds a predetermined value, the tear seam 46 is broken and the communication portion 38A is opened. Then, the gas from the inflator 22 is supplied to the main bag 26 and the sub bag 28 through the communication portion 38A. Thus, the sub bag 28 is deployed in front of the vehicle with respect to the knee K of the occupant P so as to cover the high-pressure deployment part 40 from the rear of the vehicle, and the main bag 26 is deployed in front of the vehicle with respect to the upper body U of the occupant P.

  The knee airbag 50 including the subbag 28 and the high-pressure deployment part 40 restrains the knee K of the occupant P that has moved to the front of the vehicle due to a frontal collision of the automobile V. At this time, the relatively low-pressure sub-bag 28 softly receives the knee K, and the reaction force is supported by the instrument panel 16 via the high-pressure deployment part 40 having a relatively high internal pressure. As a result, the knee K of the seated occupant P is protected during a frontal collision of the automobile V.

  In particular, in the passenger airbag device 10, the check valve 42 is provided in the communication hole 36 </ b> A that is a gas inlet to the high-pressure deployment portion 40, so that the internal pressure of the high-pressure deployment portion 40 is increased as the knee K is restrained. Even when the check valve is raised, the state where the check valve 42 closes the communication hole 36A is maintained. For this reason, the internal pressure fall (gas discharge | emission) of the high pressure expansion | deployment part 40 accompanying restraint of the knee K is suppressed, and the knee K of the seated passenger | crew P is protected more favorably.

  On the other hand, the upper body U of the occupant P is restrained by the inflated and deployed main bag 26 to absorb shock. Accordingly, the passenger P is well protected by the passenger seat airbag device 10. In particular, in the passenger seat airbag device 10, as shown in FIG. 2, gas is supplied (injected) toward both sides in the vehicle width direction in the main bag 26 through the pair of left and right communication portions 38 </ b> A. For this reason, compared with the configuration in which gas is supplied to the rear of the vehicle, the deployment force (deployment speed) of the main bag 26 toward the rear of the vehicle is suppressed, and to the occupant P when restraining the upper body U of the seated occupant P The load (load) is reduced.

  Here, in the airbag device 10 for the passenger seat, an internal pressure difference is set between the sub bag 28 and the high-pressure deploying portion 40 constituting the knee airbag 50 for protecting the knee K of the occupant P. The amount of gas in the knee airbag 50 for securing the knee protection performance can be reduced.

  That is, the knee airbag 50 deployed in a narrow space between the instrument panel 16 and the knee K has a small capacity, but the knee K abuts against the instrument panel 16 (with the bottom of the knee airbag 50 itself). ), The main bag 26 is deployed at a high pressure. In this case, in the comparative example in which the entire knee airbag is inflated and deployed at a high pressure, the amount of gas supplied to the knee airbag increases. In contrast, in the airbag device 10 for the passenger seat, the high-pressure deployment part 40 is inflated and deployed in the sub-bag 28 as described above, so the gas amount for securing the knee protection performance equivalent to that of the comparative example is reduced. can do. That is, in the comparative example described above, an inflator having a capacity equivalent to the sum of the capacities of two inflators for inflating and deploying the upper body restraining airbag and the knee airbag independently is required. In the apparatus 10, the required knee protection performance can be ensured by using the inflator 22 having a smaller capacity than the sum of the capacities of the two inflators.

  On the other hand, the main bag 26 that is inflated and deployed in a wide space (long in the front and rear direction) between the windshield glass 14 and the upper body U of the occupant P has a sufficient shock absorbing stroke even at a low pressure. Can be well protected.

  As described above, in the passenger seat airbag device 10 according to the first embodiment, the upper body U and the knees K of the occupant P can be protected while reducing the gas amount of the airbag 2.

  Further, in the passenger airbag device 10, the high-pressure deployment part 40 is deployed on the instrument panel 16 side in the sub-bag 28. In other words, the front part of the knee airbag 50 in the vehicle front-rear direction is relative to the rear part. Since the high pressure portion is used, the restraining reaction force can be supported by the high pressure deployment portion 40 while the knee K is softly received by the sub bag 28. Further, after the consumption of the buffer stroke by the sub bag 28, the knee interferes with the instrument panel 16 due to the restraint of the knee K by the high-pressure deployment part 40 having a relatively high internal pressure (a high load acts on the knee K). Is prevented or effectively suppressed.

  Furthermore, in the passenger airbag device 10, the gas in the inflator 22 is supplied directly to the high-pressure deployment unit 40 through the gas supply flow path unit 38 (without passing through the main bag 26 and the sub bag 28). The high-pressure deployment part 40 having a relatively high internal pressure for load support is inflated and deployed in a short time from the start of operation of the inflator 22. Further, in the initial operation of the inflator 22, the gas supply to the high-pressure deployment unit 40 is prioritized by the high-pressure unit preferential deployment structure 44, so that the high-pressure deployment unit 40 is inflated and deployed in a short time from the start of operation of the inflator 22. . These effectively protect the occupant's knees.

  Moreover, in the airbag device 10 for the passenger seat, gas is supplied to the high pressure deployment portion 40 through the gas supply flow path portion 38 without passing through the main bag 26 and the sub bag 28, and the internal pressure of the high pressure deployment portion 40 is a predetermined internal pressure. Exceeding the internal pressure of the gas supply flow path section 38, the internal pressure of the high-pressure deployment section 40 is reduced to the sub bag 28 with a simple structure in which the gas discharge from the high-pressure deployment section 40 is suppressed (prohibited) by the check valve 42. Can be set higher than the internal pressure.

  Furthermore, in the passenger airbag device 10, the high-pressure deployment part 40 is a single bag having a width that covers both knees K of the occupant P, and thus has a simple structure (bag shape including a gas supply path). Thus, each of the main bag 26, the sub bag 28, and the high-pressure deployment part 40 can be expanded and deployed by supplying gas.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. Note that parts and portions that are basically the same as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and description thereof is omitted. 3 shows a passenger airbag device 60 according to the second embodiment of the present invention in a side sectional view corresponding to FIG. 1, and FIG. 4 shows a passenger airbag device. The airbag 62 which comprises 60 is shown by the rear surface sectional view corresponding to FIG.

  As shown in these drawings, the airbag 62 constituting the passenger seat airbag device 60 for the passenger seat includes the main bag 26 and the subbag 28, and the airbag 20 constituting the passenger seat airbag device 10. And different from the airbag 20 in that an inner tube 64 is provided instead of the inner tube 34. The inner tube 64 is different from the inner tube 34 in that it includes a tether 66, a gas supply flow path portion 68, and a high pressure deployment portion 70 instead of the tether 36, the gas supply flow passage portion 38, and the high pressure deployment portion 40.

  As shown in FIG. 4, a pair of left and right high-pressure deployment portions 70 are provided corresponding to the left and right knees K. Therefore, the gas supply flow path portion 68 is a branch portion 68B that is bifurcated on the opposite side to the inflator 22 with respect to the communication portion 68A communicating with the main bag 26 and the sub bag 28. It is continued to the corresponding high-pressure deployment portions 70 on the left and right. Further, the tethers 66 are respectively provided in the left and right branch portions 68B, and check valves 42 are provided around the communication holes 66A that communicate the gas supply flow path portion 68 and the high-pressure deployment portion 70, respectively. .

  Thus, in the passenger airbag device 60, when the inflator 22 is operated, gas is supplied to the left and right high-pressure deployment portions 70 through the gas supply flow path 68, and the left and right high-pressure deployment portions 70 are left and right. The vehicle is inflated and deployed in front of the vehicle with respect to the knee K.

  In the passenger seat airbag device 60 described above, the knee airbag 72 is configured by the sub bag 28 and the left and right high-pressure deployment portions 70. Further, in the inner tube 64, the high-pressure part preferential deployment structure 44, that is, the tear seam 46 is provided in the communication part 68A of the gas supply flow path part 68. Other configurations of the passenger seat airbag device 60 are the same as the corresponding configurations of the passenger seat airbag device 10.

  Therefore, the passenger seat airbag device 60 according to the second embodiment also basically has the passenger seat according to the first embodiment except for the operational effect of the high-pressure deployment part 40 being formed of a single bag. The same effect can be obtained by the same operation as that of the airbag apparatus 10 for a vehicle. Further, in the passenger seat airbag device 60, the knee airbag 72 is configured to have the left and right high-pressure deployment portions 70 corresponding to the left and right knees K. In other words, the vehicle front of the left and right knees K is fronted. Since the high-pressure deployment part 70 is arranged only in the above, the amount of gas for ensuring the required knee protection performance can be further reduced.

  In each embodiment, an example in which the gas supply flow path portion 38 and the check valve 42 (and the high pressure portion priority deployment structure 44) are provided as the internal pressure difference providing structure has been described, but the present invention is not limited to this. For example, the main bag 26, the sub bag 28, and the high-pressure deployment unit 40 may be configured to receive an internal pressure difference by receiving gas supply from individual inflators. Even in this case, the sum of the capacities of the inflators is reduced with respect to the sum of the capacities of the two inflators for inflating and deploying the body restraining airbag and the knee airbag according to the comparative example. Moreover, the high pressure part preferential deployment structure 44 is not limited to the structure provided with the tear seam 46, For example, the communicating part 38A is comprised so that resistance of gas flow may become larger than the communicating hole 36A (The magnitude | size of a diameter is varied. ) Or the like.

  In each of the above-described embodiments, an example in which the main bag 26 is a so-called twin-chamber airbag in which the left and right bags are connected has been described. However, the present invention is not limited to this example. It is good also as a structure which is what is called a single chamber structure airbag which has a single chamber.

  Further, in each of the above-described embodiments, the example in which the airbag device according to the present invention is applied to the passenger seat airbag devices 10 and 60 has been described. However, the present invention is not limited to this example. Such an airbag apparatus can be applied to a seat in the center in the vehicle width direction among seats in which three passengers can be seated in the vehicle width direction. In addition, such a central seat can be regarded as being included in the passenger seat in the present invention.

10 Airbag device for passenger seat (airbag device)
16 Instrument panel 22 Inflator 26 Main bag (first bag)
28 Sub bag (second bag)
38 Gas supply channel (gas supply channel)
40 High-pressure deployment part (third bag)
42 Check valve (gas emission control means)
60 Airbag device for passenger seat 68 Gas supply channel (gas supply channel)
70 High-pressure deployment part (third bag)

Claims (5)

A first bag that restrains the upper body of the vehicle occupant from the front side in the vehicle front-rear direction by being inflated and deployed upon receiving gas supply;
A second bag that has a smaller capacity than the first bag, and that is inflated and deployed by receiving gas supply from a folded state, thereby restraining the occupant's knee from the front side in the vehicle front-rear direction;
A third bag that has a smaller capacity than the second bag, receives a gas supply from a folded state, and is inflated and deployed in the second bag;
An inflator that generates gas to be supplied to the first bag, the second bag, and the third bag;
An internal pressure difference providing structure for causing the internal pressure of the third bag to be higher than the internal pressure of the second bag when at least the second bag restrains a knee of a vehicle occupant;
An airbag device comprising: The second bag is configured to be inflated and deployed on the rear side of the vehicle front-rear direction with respect to the instrument panel,
The airbag apparatus according to claim 1, wherein the third bag is configured to be inflated and deployed on the instrument panel side in the second bag. The internal pressure difference providing structure is:
A gas supply path for directly supplying the gas from the inflator to the third bag;
A gas discharge suppressing means for suppressing discharge of gas from the third bag when the internal pressure of the third bag exceeds a predetermined value;
The airbag apparatus of Claim 1 or Claim 2 comprised including this.   The airbag device according to any one of claims 1 to 3, wherein the third bag is a single bag having a width capable of restraining both knees of the occupant.   The airbag device according to any one of claims 1 to 3, wherein the third bag is provided in a pair of left and right so as to individually restrain both knees of the occupant.

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