JP7748834B2 - Airbag device - Google Patents

Description

The present invention relates to an airbag device.

Airbag devices that are installed in vehicles such as automobiles and inflate and deploy in the event of a vehicle collision to protect occupants include passenger airbag devices in which an airbag inflates and deploys in front of and toward the passenger seated in the front passenger seat during a frontal collision, thereby catching and protecting the occupant as they move forward, and side airbag devices in which an airbag inflates and deploys between the side wall inside the vehicle cabin and the seated occupant during a side collision.

Usually, in its initial state, an airbag is stored in a fixed member (housing) in a folded state, and the fixed member storing the airbag is covered with a cover to prevent it from being visible to occupants. The fixed member is attached to the cover by inserting a hook of the fixed member into an opening in the cover (see, for example, Patent Documents 1 and 2).

Furthermore, for example, Patent Document 3 discloses an airbag device that has a housing that stores an airbag and a cover that covers the airbag, with a hook that protrudes from the side wall of the housing being inserted into a locking hole formed in the side wall (mounting wall) of the cover. In Patent Document 1, when inserting the hook into the locking hole, the side wall of the cover is bent outward by the hook of the housing, and the housing is inserted into the space formed by the side wall of the cover, and the hook is pushed into a position where it protrudes outward beyond the side wall from the locking hole.

Japanese Patent Application Laid-Open No. 2003-25943 JP 2018-202882 A JP 2015-123795 A

However, with the airbag device described in Patent Document 3, if the housing is pushed in too forcefully when assembling it to the cover, the hooks may end up inserted further than the locking holes, or, after one hook is locked into the locking hole, the first hook may come loose when the other hook is pushed into the side wall, causing it to end up inserted further. In either case, the housing must be pulled out of the cover, increasing the amount of work required.

The present invention was made in consideration of the above-mentioned current situation, and aims to provide an airbag device that makes it easy to assemble the hook of the fixing member that stores the airbag into the opening in the cover that covers the airbag.

One aspect of the present invention comprises an inflator that generates gas, an airbag that is folded and stored and inflates and deploys using the gas, a fixing member that stores the folded airbag, and a cover that covers the airbag stored in the fixing member, wherein the cover has a lid portion that faces the interior of the vehicle cabin, an outer peripheral wall portion whose base end is connected to the back surface of the lid portion and whose tip end protrudes from the back surface toward the vehicle body, openings provided in each of a pair of opposing wall portions of the outer peripheral wall portion, and a slit provided inside at least one of the pair of wall portions and closer to the lid portion than the opening. the fixing member has a fixing portion that fixes the inflator and the airbag; an inner wall portion that is provided from the fixing portion toward the back surface of the lid portion and at least a portion of which is located inside the outer peripheral wall portion; and a hook that is provided at the tip of the inner wall portion, penetrates the opening from the inside to the outside of the outer peripheral wall portion, and bends toward the tip side of the outer peripheral wall portion; the restricting portion protrudes inside the outer peripheral wall portion beyond the tip side opening edge that forms the opening, and the tip side end face of the restricting portion is continuous with the base side opening edge that forms the opening.

This invention provides an airbag device that makes it easy to assemble the hook of the fixing member that stores the airbag into the opening in the cover that covers the airbag.

1 is a cross-sectional view schematically illustrating an initial state of an airbag device according to a first embodiment attached to a vehicle, as viewed from the vehicle width direction. 3 is a schematic diagram of a cover included in the airbag device according to the first embodiment, viewed from the upper left rear. FIG. 3 is a perspective view of a restricting portion of the cover in FIG. 2. FIG. 3 is a schematic diagram of a cover included in the airbag device according to the first embodiment, viewed from a diagonally lower front right side. FIG. 2 is an enlarged view of the hook on the rear side of the vehicle shown in FIG. 1 and its vicinity. 3 is a schematic diagram of a fixing member included in the airbag device according to the first embodiment, viewed from an upper left rear side. FIG. 10 is a cross-sectional view showing the cover and the fixing member during assembly, illustrating a first step of a process in which the hook on the vehicle rear side of the fixing member is hooked into the opening on the vehicle rear side of the cover. FIG. 10 is a cross-sectional view showing the cover and the fixing member during assembly, illustrating a second stage of the process of hooking the hook on the vehicle rear side of the fixing member into the opening on the vehicle rear side of the cover. FIG. 10 is a schematic cross-sectional view showing the cover and the fixing member during assembly, illustrating a third stage of the process of hooking the hook on the vehicle rear side of the fixing member into the opening on the vehicle rear side of the cover. FIG. 10 is a cross-sectional view showing the cover and the fixing member during assembly, illustrating the fourth stage (after the hooks are completely engaged) of the process of hooking the hooks on the vehicle rear side of the fixing member into the openings on the vehicle rear side of the cover. FIG. 10 is a cross-sectional view showing the cover and the fixing member during assembly, illustrating a first step of a process in which the hook on the vehicle front side of the fixing member is hooked into the opening on the vehicle front side of the cover. FIG. 10 is a cross-sectional view showing the cover and the fixing member during assembly, illustrating a second stage of the process of hooking the hook on the vehicle front side of the fixing member into the opening on the vehicle front side of the cover. FIG. 10 is a cross-sectional view showing the cover and the fixing member during assembly, illustrating a third stage of the process of hooking the hook on the vehicle front side of the fixing member into the opening on the vehicle front side of the cover. FIG. 10 is a cross-sectional view showing the cover and the fixing member during assembly, illustrating the fourth stage (after the hooks are fully engaged) of the process of hooking the hooks on the vehicle front side of the fixing member into the openings on the vehicle front side of the cover. 4 is another schematic cross-sectional view of the airbag device according to the first embodiment attached to the vehicle in an initial state, as viewed from the vehicle width direction. FIG. FIG. 16 is a cross-sectional view of the airbag device shown in FIG. 15 in a state after the airbag is inflated and deployed, as viewed from the vehicle width direction.

(Embodiment 1)
First, the initial state of the airbag device according to the first embodiment will be described with reference to FIGS. 1 to 6. FIG. 1 is a cross-sectional schematic view of the initial state of the airbag device according to the first embodiment, as viewed from the vehicle width direction. FIG. 2 is a schematic view of a cover included in the airbag device according to the first embodiment, as viewed from the upper left rear. FIG. 3 is a perspective view of a restricting portion of the cover in FIG. 2. FIG. 4 is a schematic view of the cover included in the airbag device according to the first embodiment, as viewed from the lower right front. FIG. 5 is an enlarged view of the hook on the vehicle rear side shown in FIG. 1 and its vicinity. FIG. 6 is a schematic view of a fixing member included in the airbag device according to the first embodiment, as viewed from the upper left rear.

As shown in FIG. 1, the airbag device 100 of embodiment 1 is a passenger seat airbag device that is arranged to cover an opening on the top surface of an instrument panel AA located in front of the passenger seat and includes an inflator (gas generator) 1 that generates gas, a folded, bag-shaped airbag 2, a fixing member 10 that stores the folded airbag 2, and a cover 50 that covers the airbag 2 stored in the fixing member 10. In this specification, the term "initial state" refers to the state before the inflator 1 is ignited, i.e., before the airbag 2 is inflated and deployed.

The inflator 1 is activated when the vehicle experiences a frontal collision. First, when a collision detection sensor mounted on the vehicle detects a frontal collision, the ECU (Electronic Control Unit) calculates the signal sent from the collision detection sensor and determines the level of the collision. If the determined level of the collision corresponds to a level that requires the airbag 2 to be inflated, the inflator 1 is ignited, and gas is generated by a chemical reaction caused by combustion. The generated gas is released into the airbag 2 from the gas outlet holes of the inflator 1. Note that there are no particular limitations on the type of inflator 1, and examples that can be used include pyrotechnic inflators that use gas generated by burning a gas generating agent, stored inflators that use compressed gas, and hybrid inflators that use a mixture of gas generated by burning a gas generating agent and compressed gas.

The airbag 2 is a bag-shaped body, and before the inflator 1 is activated, it is folded and stored within a fixing member 10 located inside the upper surface of the instrument panel AA. When the inflator 1 is activated, the gas generated by the inflator 1 fills the interior of the airbag 2, causing the airbag 2 to unfold and inflate. As a result, the airbag 2 pushes open the lid portion 51 attached to the cover 50, and inflates and deploys inside the vehicle cabin.

The airbag 2 can be formed from threads such as nylon 66 or polyethylene terephthalate (PET). The surface of the airbag 2 may also be coated with an inorganic material such as silicone to improve heat resistance and airtightness.

A metal annular clamping plate 3 with an inflator 1 mounting hole is positioned inside the underside of the airbag 2. The clamping plate 3, airbag 2, fixing portion 11 of fixing member 10, and flange portion 1a of inflator 1 are secured together by bolts 4 passing through them and fastened with nuts 5.

The fixing member 10 is attached to the outer wall portion 52 of the cover 50, which protrudes toward the inside (vehicle body side) of the instrument panel AA, by multiple hooks 30a and 30b provided on the inner wall portion 13. The fixing member 10 also has an attachment portion 16 protruding from its underside, and the attachment portion 16 is attached to the vehicle body member BB by the fixing member CC.

The cover 50 and fixing member 10 will be described in detail below in that order.

As shown in Figures 1 to 4, the cover 50 is a lid material molded from a synthetic resin such as a thermoplastic resin, and has a lid portion 51 facing the interior of the vehicle cabin, an outer peripheral wall portion 52 whose base end 52a is connected to the back surface 51a of the lid portion 51 and whose tip end 52b protrudes from the back surface 51a toward the vehicle body, openings 54a and 54b provided in a pair of opposing wall portions 53a and 53b of the outer peripheral wall portion 52, a restricting portion 70 provided inside the wall portion 53a and closer to the lid portion 51 than the opening 54a, and a flange portion 90 protruding outward from the peripheral edge of the lid portion 51.

The lid portion 51 is a rectangular portion positioned above the folded airbag 2 so as to cover the airbag 2. The back surface 51a of the lid portion 51 has a cutout portion 51b, such as a linear groove, that allows the airbag 2 to inflate and deploy. The lid portion 51 is divided into a pair of door portions 51c located on both sides of the lid portion 51. When the cutout portion 51b breaks due to the airbag 2 inflating and deploying, the pair of door portions 51c rotate around hinges 51d.

The flange portion 90 is a rectangular frame-shaped portion provided around the lid portion 51, and the back surface 90a of the flange portion 90 is provided with multiple fixing members 91, such as hooks or clips.

The lid portion 51 and flange portion 90 are attached to the instrument panel AA by fixing members 91 so as to close an opening provided in the instrument panel AA. The lid portion 51 and flange portion 90 form a common surface, and together with the instrument panel AA, form the front of the passenger seat, which is part of the interior wall that forms the vehicle interior space.

The outer peripheral wall portion 52 is a standing wall that protrudes from the back surface 51a of the lid portion 51 toward the airbag 2 (vehicle body side) and is formed to surround the folded airbag 2 and the fixing member 10. At least a portion of the folded airbag 2 is disposed within the space 58 formed by the outer peripheral wall portion 52. The outer peripheral wall portion 52 surrounds the entire periphery of the folded airbag 2 and also functions as a guide member that controls the deployment of the airbag 2 when it is inflated and deployed. The outer peripheral wall portion 52 is also a peripheral wall portion that surrounds the outside of the inner wall portion 13 of the fixing member 10.

The outer peripheral wall portion 52 has a base end 52a on the lid portion 51 side and a tip end 52b on the vehicle body side. The base end 52a side of the space 58 is covered by the lid portion 51, while the tip end 52b side of the space 58 is open, forming an opening 59. The opening 59 serves as an insertion port through which the fixing member 10 is inserted when assembling the fixing member 10 to the cover 50.

In addition to walls 53a and 53b, the outer wall 52 further has a pair of opposing walls 53c and 53d. Each wall 53a, 53b, 53c, and 53d is formed in a rectangular shape, and the outer wall 52 is formed in a rectangular cylindrical shape by walls 53a, 53b, 53c, and 53d.

Walls 53a and 53b are arranged substantially parallel to each other and face each other across a space 58. Wall 53a is located on the rear side of the vehicle (occupant side), and wall 53b is located on the front side of the vehicle. Walls 53c and 53d are also arranged substantially parallel to each other and face each other across a space 58. Walls 53a and 53b are arranged so as to intersect with walls 53c and 53d, in this case perpendicular to them.

Multiple openings 54a are provided in the wall portion 53a. The openings 54a are through-holes that penetrate the wall portion 53a and are arranged in a row in a direction D2 that is perpendicular to the insertion direction D1 of the fixing member 10 into the cover 50. Here, direction D2 is parallel to the vehicle width direction. Note that only one opening 54a may be provided in the wall portion 53a.

Multiple openings 54b are provided in the wall portion 53b. The openings 54b are through-holes that penetrate the wall portion 53b and are arranged in a row in the direction D2 perpendicular to the insertion direction D1. Note that only one opening 54b may be provided in the wall portion 53b.

The same number of openings 54a and 54b are provided on the walls 53a and 53b, respectively, and are arranged in the same positions facing each other. Furthermore, the openings 54a and 54b are longitudinal, with both ends 55 in a direction D2 perpendicular to the insertion direction D1, and here are formed in a roughly rectangular shape with their short sides facing the insertion direction D1.

As shown in FIG. 5 , the distal opening edge 56 forming the opening 54a approaches the base end 52a of the outer peripheral wall 52 as it moves from the inside to the outside of the outer peripheral wall 52. That is, the end face 56a of the distal opening edge 56 does not directly face the end face 57a of the base opening edge 57 forming the opening 54a, but is inclined toward the space 58. The distal opening edge 56 is the portion of the edge of the wall 53a that surrounds the opening 54a (forming the opening 54a) and is located on the distal end 52b side. The base opening edge 57 is the portion of the edge of the wall 53a that surrounds the opening 54a (forming the opening 54a) and is located on the base end 52a side.

The restricting portion 70 is a protrusion that protrudes from the inner surface 53aa of the wall portion 53a toward the airbag 2 (space 58), and restricts (limits) excessive movement of the fixing member 10, such as when the fixing member 10 is pushed too far toward the lid portion 51 during assembly. The restricting portion 70 is provided in at least the area between the opening 54a and the base end 52a. Here, multiple restricting portions 70, for example, two, are provided for each opening 54a (adjacent to each opening 54a), but only one may be provided for each opening 54a. Furthermore, one or more restricting portions 70 may be provided for at least one opening 54a.

As shown in FIG. 5, the restricting portion 70 protrudes further inward (toward the airbag 2, toward the space 58) from the outer peripheral wall portion 52 (wall portion 53a) than the tip-side opening edge 56 that forms the opening 54a (the opening to which the restricting portion 70 is adjacent). That is, the restricting portion 70 protrudes further toward the space 58 than the inner surface 53aa of the wall portion 53a on both the tip end 52b side and the base end 52a side of the outer peripheral wall portion 52 relative to the opening 54a.

Furthermore, as shown in FIG. 5, the distal end surface 70a of the restricting portion 70 is continuous with the proximal opening edge 57 that forms the opening 54a (the opening to which the restricting portion 70 is adjacent). Here, the distal end surface 70a of the restricting portion 70 and the end surface 57a of the proximal opening edge 57 that forms the opening 54a are located on a common plane P1, which is set in a direction approximately perpendicular to the direction in which the wall portion 53a protrudes from the back surface 51a of the lid portion 51. However, it is sufficient that the distal end surface 70a and the end surface 57a of the proximal opening edge 57 are smoothly connected without any steps, protrusions, or depressions between them. In other words, it is sufficient that the distal end surface 70a and the end surface 57a of the proximal opening edge 57 are adjacent and share the same boundary line (usually a straight line). For example, the distal end face 70a and the end face 57a of the proximal opening edge 57 may intersect at a predetermined angle (usually greater than 90° and less than 180°) on the same boundary line. Note that the distal end face 70a of the restricting portion 70 is the end face of the restricting portion 70 that is located on the distal end 52b side of the outer peripheral wall portion 52.

As shown in FIG. 1, in this embodiment, the folded airbag 2 is positioned beyond the restricting portion 70. That is, at least a portion of the lid portion 51 side of the folded airbag 2 is located closer to the lid portion 51 than the restricting portion 70. As a result, the airbag 2 is less likely to get caught on the restricting portion 70 when inflating and deploying, allowing the airbag 2 to inflate and deploy smoothly. On the other hand, in the airbag device described in Patent Document 1, a convex portion is provided closer to the lid portion than the folded airbag, so there is a risk that the airbag will get caught on the convex portion when inflating and deploying.

As shown in Figures 1 and 6, the fixing member 10 is a housing molded from a metal material and includes a fixing portion 11 that fixes the inflator 1 and the airbag 2, an inner wall portion 13 that extends from the fixing portion 11 toward the back surface 51a of the lid portion 51 and at least a portion of which is located inside the outer peripheral wall portion 52, and hooks 30a and 30b that are provided at the tip end 13b of the inner wall portion 13, pass through openings 54a and 54b from the inside to the outside of the outer peripheral wall portion 52, and bend toward the tip end 52b of the outer peripheral wall portion 52.

The fixing portion 11 is the rectangular bottom portion of the fixing member 10, and supports the folded airbag 2 from below. A mounting hole 12 for the inflator 1 is provided in the center of the fixing portion 11.

The inner wall portion 13 is a standing wall that protrudes from the surface 11a of the fixing portion 11 (the surface facing the lid portion 51) toward the airbag 2 (toward the vehicle interior) and is formed to surround the folded airbag 2. A portion (lower portion) of the folded airbag 2 is disposed within the space 17 formed by the inner wall portion 13. The inner wall portion 13 is also a peripheral wall portion provided inside the outer peripheral wall portion 52 of the cover 50. A portion of the inner wall portion 13, here the portion of the inner wall portion 13 facing the lid portion 51, is disposed inside the outer peripheral wall portion 52 (within the space 58). Note that the entire inner wall portion 13 may also be disposed inside the outer peripheral wall portion 52 (within the space 58).

The inner wall portion 13 has a base end portion 13a on the fixing portion 11 side and a tip end portion 13b on the lid portion 51 side. The fixing portion 11 is located on the base end portion 13a side of the space 17, and the tip end portion 13b side of the space 17 is open, forming an opening 18. The opening 18 serves as an insertion port through which the folded airbag 2 is inserted when assembling the airbag 2 to the fixing member 10.

The inner wall portion 13 has a pair of opposing walls 14a and 14b and a pair of opposing walls 14c and 14d. Each of the walls 14a, 14b, 14c, and 14d is rectangular, and the inner wall portion 13 is formed into a rectangular tube by the walls 14a, 14b, 14c, and 14d. However, the two corners of the walls 14c and 14d on the fixing portion 11 side are open to form rectangular openings 15. The inner wall portion 13 is also formed slightly smaller than the outer peripheral wall portion 52 so that it can be inserted into the space 58 surrounded by the outer peripheral wall portion 52. Note that, although the inner wall portion 13 surrounds the entire periphery of the folded airbag 2 here, it is not necessary to surround the entire periphery of the folded airbag 2; for example, it may not have walls 14c and 14d.

Walls 14a and 14b are arranged substantially parallel to each other and face each other across space 17. Wall 14a is located on the rear side of the vehicle (occupant side), and wall 14b is located on the front side of the vehicle. Walls 14c and 14d are also arranged substantially parallel to each other and face each other across space 17. Walls 14a and 14b are arranged so as to intersect with walls 14c and 14d, in this case, perpendicular to them.

Multiple hooks 30a are provided on the wall portion 14a. The hooks 30a are hook-shaped members provided on the outside of the tip portion 13b of the inner wall portion 13, and are provided in the same number as the openings 54a in the outer wall portion 52, corresponding to the openings 54a. Each hook 30a has a protruding portion 31 that protrudes from the outer surface of the tip portion 13b of the wall portion 14a to the outside of the inner wall portion 13, a bent portion 32 where the protruding portion 31 is bent toward the tip portion 52b of the outer wall portion 52, i.e., toward the base end portion 13a of the inner wall portion 13, and an extension portion 33 that extends from the bent portion 32 toward the tip portion 52b of the outer wall portion 52 (toward the base end 13a of the inner wall portion 13). To ensure strength, the protruding portion 31 has a recessed portion 35 recessed toward the base end 13a of the inner wall portion 13. Instead of the recess 35, the protrusion 31 may have a protrusion that protrudes toward the lid 51.

Multiple hooks 30b are provided on the wall portion 14b. Similarly, the hooks 30b are hook-shaped members provided on the outside of the tip portion 13b of the inner wall portion 13, and are provided in the same number as the openings 54b in the outer wall portion 52, corresponding to the openings 54b. The hooks 30b are formed in the same shape as the hooks 30a.

As shown in FIG. 5, the length (distance) L1 between the distal opening edge 56 that forms the opening 54a and the proximal opening edge 57 that forms the opening 54a is shorter than the length L2 from the bent portion 32 of the hook 30a to the tip 34 of the hook 30a. Note that length L1 is the minimum length of the opening 54a in the insertion direction D1 of the fixing member 10 into the cover 50, and is, for example, the length between the outer edge of the distal opening edge 56 and the outer edge of the proximal opening edge 57, as shown in FIG. 5.

Here, using Figures 7 to 14, we will explain how to assemble the fixing member 10 to the cover 50. Figures 7 to 14 are schematic cross-sectional views showing the cover and fixing member during assembly. Figures 7 to 10 show each stage of the process of hooking the hook on the rear side of the fixing member into the opening on the rear side of the cover, with Figure 7 showing the first stage, Figure 8 showing the second stage, Figure 9 showing the third stage, and Figure 10 showing the fourth stage (after the hooks have been fully engaged). Figures 11 to 14 show each stage of the process of hooking the hook on the front side of the fixing member into the opening on the front side of the cover, with Figure 11 showing the first stage, Figure 12 showing the second stage, Figure 13 showing the third stage, and Figure 14 showing the fourth stage (after the hooks have been fully engaged). Note that Figures 7 to 14 omit illustrations of components other than the cover 50 and fixing member 10.

First, as shown in FIG. 7 , the hook 30a of the fixing member 10 and a portion of the inner wall portion 13 (wall portion 14a) are inserted into the opening 59 formed by the outer wall portion 52 of the cover 50 until one of the hooks 30a of the fixing member 10, to which the folded airbag and inflator are fixed, abuts against the tip end surface 70a of the restricting portion 70 of the cover 50. Next, as shown in FIG. 8 , with the fixing member 10 tilted so that the fixing portion 11 of the fixing member 10 faces outward from the outer wall portion 52, the hook 30a is slid along the tip end surface 70a of the restricting portion 70 until the tip 34 of the hook 30a protrudes outward from the opening 54a in the outer wall portion 52 (wall portion 53a). Then, as shown in FIG. 9 , while the fixing member 10 is tilted, the tip of the hook 30a is moved further outward beyond the opening 54a. As a result, as shown in Figure 10, the hook 30a penetrates from the inside to the outside of the outer wall portion 52 (wall portion 53a) and becomes caught in the opening 54a.

When the hook 30a is hooked into the opening 54a, the distal end face 70a of the restricting portion 70 is continuous with the proximal opening edge 57 that forms the opening 54a (the opening to which the restricting portion 70 is adjacent). This allows the hook 30a to slide while successively abutting against the distal end face 70a and proximal opening edge 57 of the restricting portion 70, making it easy to change the position and posture of the hook 30a.

Then, as shown in FIG. 11, the other hook 30b is brought into contact with the tip of wall portion 53b to pass through opening 54b. Next, as shown in FIG. 12, the hook 30b is pushed into opening 59 formed by the outer wall portion 52 while elastically deforming the outer wall portion 52. Then, as shown in FIG. 13, the hook 30b is pushed into space 58 inside the outer wall portion 52 while the tip of the hook 30b protrudes outward from opening 54b in wall portion 53b, thereby passing the hook 30b through opening 54b. At this time, the fixing member 10 rotates around hook 30a, which is supported by abutting against the tip end surface 70a of the restricting portion 70. As a result, the assembly of the fixing member 10 to the cover 50 is completed, as shown in FIG. 14.

After assembly, the airbag device 100 has a so-called floating structure. In other words, before assembly into a vehicle, such as in its delivery state, the hooks 30a and 30b of the fixing member 10 are hooked into the openings 54a and 54b in the outer wall portion 52 of the cover 50, respectively, as shown in FIG. 14, allowing the airbag device 100 to be handled as a single component. After assembly into a vehicle, as shown in FIG. 1, the fixing member 10 is fixed to the vehicle body member BB, and the cover 50 is attached to the instrument panel AA (or the trim in the case of a rear seat side airbag device), allowing the hooks 30a and 30b of the fixing member 10 to float (float) while penetrating the openings 54a and 54b in the outer wall portion 52 of the cover 50. In other words, in the initial state of the airbag device 100 after assembly into the vehicle, the fixing member 10 is not in contact with the cover 50. This allows the airbag device 100 to be assembled into the vehicle without being affected by dimensional variations within the vehicle.

Next, the operation of the airbag device 100 will be described.

Figure 15 is another schematic cross-sectional view of the airbag device according to embodiment 1 installed in a vehicle in its initial state, as viewed from the vehicle width direction. As shown in Figure 15, in the initial state, the airbag device 100 is positioned so as to cover the opening in the upper surface of the instrument panel AA, and is installed below the windshield DD.

Figure 16 is a cross-sectional view of the airbag device shown in Figure 15, viewed from the vehicle width direction, showing the state after the airbag has been inflated and deployed. When the vehicle collides head-on with an obstacle (e.g., another vehicle) and inflator 1 is activated, gas generated by inflator 1 is introduced into airbag 2, causing the airbag 2 to unfold and inflate. When the force applied by the inflated airbag 2 breaks the cutout portion 51b of the lid portion 51, the pair of door portions 51c rotate about hinges 51d toward the passenger compartment and open, and the airbag 2 inflates and deploys within the passenger compartment, as shown in Figure 16.

When the airbag 2 inflates and deploys, particularly when the airbag 2 is fully inflated and deployed, as shown in Figure 16, the reaction force from the inflation and deployment of the airbag 2 causes the occupant-side portion of the instrument panel AA to deform, and the airbag 2 presses the lid portion 51 from the inside of the vehicle compartment toward the vehicle body. As the lid portion 51 is pressed, the outer peripheral wall portion 52 also moves toward the fixing member 10, but the hook 30a abuts against the tip end face 70a of the restricting portion 70, preventing the outer peripheral wall portion 52 from moving excessively.

As described above, in this embodiment, the distal end surface 70a of the restricting portion 70 is continuous with the base end opening edge 57 that forms the opening 54a. Therefore, when assembling the fixing member 10 to the cover 50, one of the hooks 30a can be inserted into the opening 54a while abutting against the distal end surface 70a of the restricting portion 70. This prevents the hook 30a from being pushed too far toward the lid portion 51 than the opening 54a. Furthermore, when inserting the other hook 30b into the opening 54b, if the hook 30a were supported solely by the thickness of the base end opening edge 57, the hook 30a would likely slip. However, since the hook 30a can be supported not only by the base end opening edge 57 but also by the distal end surface 70a of the restricting portion 70, the hook 30a is stabilized, and the hook 30b can be assembled without coming off. Therefore, in this embodiment, the hooks 30a and 30b of the fixing member 10 that stores the airbag 2 can be easily assembled into the openings 54a and 54b of the cover 50 that covers the airbag 2.

In addition, in this embodiment, it is preferable that the hook 30a abuts against the tip end surface 70a of the restricting portion 70 when the airbag 2 inflates and deploys. As described above, when the airbag 2 inflates and deploys, the folded airbag 2 is pushed open by gas from the inflator 1, forcefully inflating and deploying into the vehicle cabin. The recoil from the momentum of the subsequent deployment causes the inflated airbag 2 to move toward the lid 51, pressing the lid 51 from the inside of the vehicle cabin toward the vehicle body. As the lid 51 is pressed, the outer peripheral wall 52 (particularly the wall portion 53a) also moves toward the fixing member 10, but excessive movement of the outer peripheral wall 52 is suppressed by the hook 30a abutting against the tip end surface 70a of the restricting portion 70. As a result, the cover 50 can be prevented from coming off the fixing member 10 when the airbag 2 inflates and deploys.

Furthermore, in this embodiment, it is preferable that the tip opening edge 56 forming the opening 54a approaches the base end 52a of the outer peripheral wall portion 52 as it moves from the inside to the outside of the outer peripheral wall portion 52. This allows the opening 54a to be made smaller, thereby ensuring the strength of the outer peripheral wall portion 52. When assembling the fixing member 10 to the cover 50, as shown in Figures 7 to 10, the hook 30a penetrates the opening 54a in a state in which the fixing member 10 is rotated around the abutment point between one hook 30a and the tip end face 70a of the restricting portion 70 as a base point. Therefore, the hook 30a can penetrate the opening 54a even if the tip opening edge 56 approaches the base end 52a of the outer peripheral wall portion 52 as it moves from the inside to the outside of the outer peripheral wall portion 52.

Furthermore, in this embodiment, it is preferable that the length L1 between the distal opening edge 56 that forms the opening 54a and the proximal opening edge 57 that forms the opening 54a is shorter than the length L2 from the bent portion 32 of the hook 30a to the tip 34 of the hook 30a. This also allows the opening 54a to be made smaller, thereby ensuring the strength of the outer wall portion 52. Furthermore, as described above, when the fixing member 10 is assembled to the cover 50, the hook 30a penetrates the opening 54a while the fixing member 10 is rotated around the abutment point between one hook 30a and the distal end face 70a of the restricting portion 70 as a base point. Therefore, even if the length L1 is shorter than the length L2, the hook 30a can penetrate the opening 54a.

Furthermore, in this embodiment, the opening 54a has a longitudinal shape having both end portions 55 in a direction D2 perpendicular to the insertion direction D1 of the fixing member 10 into the cover 50, and it is preferable that the restricting portions 70 are provided adjacent to at least both end portions 55 of the opening 54a. As a result, even if the lid portion 51 is pressed obliquely from the inside of the vehicle compartment toward the vehicle body by the inflated airbag 2 when the airbag 2 inflates and deploys, the restricting portions 70 provided adjacent to both end portions 55 can suppress excessive movement of the outer peripheral wall portion 52, thereby preventing the cover 50 from coming off the fixing member 10 due to the inflation and deployment of the airbag 2.

Other variations of this embodiment are described below.

As described above, in this embodiment, it is preferable that the restricting portion 70 be provided adjacent to at least both ends 55 of the opening 54a. In this case, there is no particular limitation on whether the restricting portion 70 is provided in areas other than the areas adjacent to both ends 55 of the opening 54a. However, from the perspective of reducing the amount of material used, it is preferable to provide the restricting portion 70 only in areas adjacent to both ends 55 of the opening 54a, as shown in Figures 3 and 4. On the other hand, the restricting portion 70 may be provided adjacent to the entire opening 54a, or adjacent to the area between adjacent openings 54a. For example, the restricting portion 70 may be provided linearly along a row of multiple openings 54a.

Furthermore, in this embodiment, the restricting portion 70 may be provided adjacent to the opening 54b of the wall portion 53b instead of the opening 54a of the wall portion 53a, or adjacent to each of the openings 54a and 54b. That is, the restricting portion 70 may be provided inside the wall portion 53b instead of the wall portion 53a, or may be provided inside each of the walls 53a and 53b. However, in a passenger seat airbag device, from the perspective of effectively suppressing excessive movement of the outer peripheral wall portion 52 when the airbag 2 is inflated and deployed, it is preferable that the restricting portion 70 be provided adjacent to at least the opening 54a of the wall portion 53a, and preferably at least inside the wall portion 53a.

Furthermore, while this embodiment describes a passenger airbag device, the airbag device of the present invention is not particularly limited to passenger airbag devices, and may be, for example, a rear seat side airbag device attached to the inside of a trim provided on the rear seat of a vehicle.

The present invention is not limited to the content described in the above embodiment. The components described in the embodiment may be deleted, added, modified, or combined as appropriate without departing from the spirit of the present invention.

1: Inflator (gas generator)
1a: Flange portion of inflator 2: Airbag 3: Clamping plate 4: Bolt 5: Nut 10: Fixing member 11: Fixing portion 11a: Surface of fixing portion 12: Mounting hole 13 of inflator: Inner wall portion 13a: Base end portion of inner wall portion 13b: Tip portions of inner wall portion 14a, 14b, 14c, 14d: Wall portion of inner wall portion 15: Opening in wall portion 16: Mounting portion 17: Space 18 formed by the inner wall portion: Openings 30a, 30b in inner wall portion: Hook 31: Protruding portion 32: Bent portion 33: Extension portion 34: Tip portion of hook 35: Recess 50: Cover 51: Lid portion 51a: Back surface of lid portion 51b: Notch portion 51c: Door portion 51d: Hinge 52: Outer wall portion 52a: Base end portion of outer wall portion 52b: Tip portions of outer wall portion 53a, 53b, 53c, 53d: Outer wall portion Wall portion 53aa: inner surfaces 54a, 54b of the wall portion: opening 55 in the wall portion: both ends 56 of the opening in the wall portion: tip-side opening edge 56a forming the opening: end face 57 of the tip-side opening edge: base-side opening edge 57a forming the opening: end face 58 of the base-side opening edge: space 59 formed by the outer peripheral wall portion: opening 70 in the outer peripheral wall: restricting portion 70a: tip-side end face 90 of the restricting portion: flange portion 90a: back surface 91 of the flange portion: fixing member 100: airbag device AA: instrument panel BB: body member CC: fixing member DD: windshield D1: insertion direction D2: direction P1 perpendicular to the insertion direction: plane L1: length L2 between the tip-side opening edge forming the opening and the base-side opening edge forming the opening: length from the bent portion of the hook to the tip of the hook

Claims (5)

an inflator that generates gas;
an airbag that is folded and stored and inflated and deployed by the gas;
a fixing member that stores the folded airbag;
a cover that covers the airbag housed in the fixing member,
The cover has a lid portion facing the interior of the vehicle cabin, an outer peripheral wall portion whose base end is connected to the back surface of the lid portion and whose tip end protrudes from the back surface toward the vehicle body, an opening provided in each of a pair of opposing wall portions of the outer peripheral wall portion, and a restricting portion provided inside at least one of the pair of wall portions and closer to the lid portion than the opening,
the fixing member has a fixing portion that fixes the inflator and the airbag, an inner wall portion that is provided from the fixing portion toward the back surface of the lid portion and at least a portion of which is disposed inside the outer peripheral wall portion, and a hook that is provided at a tip end of the inner wall portion, passes through the opening from the inside to the outside of the outer peripheral wall portion, and is bent toward the tip end side of the outer peripheral wall portion,
the restricting portion protrudes inward of the outer peripheral wall portion beyond a tip-side opening edge that forms the opening,
The airbag device according to claim 1, wherein a tip end surface of the restricting portion is continuous with a base end opening edge that forms the opening. 2. The airbag device according to claim 1,
The airbag device is characterized in that the hook abuts against the tip end surface of the restricting portion when the airbag is inflated and deployed. 3. The airbag device according to claim 1 or 2,
The airbag device is characterized in that the tip-side opening edge approaches the base end of the outer peripheral wall portion as it moves from the inside to the outside of the outer peripheral wall portion. The airbag device according to any one of claims 1 to 3,
The airbag device according to claim 1, wherein the length between the distal end opening edge and the proximal end opening edge is shorter than the length from the bent portion of the hook to the distal end of the hook. The airbag device according to any one of claims 1 to 4,
the opening has an elongated shape having both ends in a direction perpendicular to the insertion direction of the fixing member into the cover,
The airbag device is characterized in that the restricting portions are provided adjacent to at least both end portions of the opening.