JP3505885B2 - Airbag device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag device suitable for use in a passenger seat of an automobile, and more particularly to an airbag device having an improved connecting structure between a lid and a case.

[0002]

2. Description of the Related Art In a passenger airbag apparatus, a folded airbag is housed in a case (sometimes referred to as a container or a retainer), and an edge portion of a gas receiving port of the airbag is provided. It is attached to the inner surface of the case.

One side of the case is open, and the opening is covered with a lid. When the inflator arranged in the case operates to generate gas, the airbag presses the lid from the back side to open the lid, and the airbag deploys in the vehicle compartment.

A leg piece is erected from the rear surface of the lid, and the leg piece is attached to the case with rivets or bolts. A tear line may be provided on the lid to open the lid when the airbag is deployed, and the lid may be configured to tear along the tear line. In addition, the lid may be opened by removing the leg pieces from the case. Further, the lid may be opened by tearing the leg pieces.

[0005]

The conventional airbag device has the following problems (1) and (2) to be solved.

(1) When the airbag device operates, the hot gas from the inflator comes into direct contact with the edge of the airbag. Therefore, a strong and thick cloth that sufficiently withstands the hot gas is required as the base fabric of the airbag. Therefore, the folded body of the airbag was bulky. Therefore, the size of the airbag device is also large.

(2) When attaching the leg pieces of the lid to the case with rivets or bolts, it is necessary to use a large number of rivets or bolts, and it takes a lot of time and effort to assemble the airbag device.

According to another aspect of the airbag device of the present invention, there is provided a case having an opening through which the airbag passes during deployment, a gas generating inflator attached to the case, and a gas receiving port for receiving gas from the inflator. And an edge portion of the gas receiving port attached to the case, an airbag housed in the case, a lid covering the opening of the case, and a projecting portion from the back surface of the lid. ,
An airbag device having a leg portion of the lid fixed, the edge of the gas introducing port of the airbag is disposed on the outer surface of the case wraps around the open mouth of the case, the
A lid connecting plate that overlaps the edge of the gas inlet of the airbag
Is provided, and the lid connecting plate is a hook for locking the lid.
And a hook provided on the lid leg piece.
The lid is connected to the lid by engaging the engaging opening and the hook.
It is characterized by being connected to a plate .

In such an airbag device, since the edge portion of the airbag is arranged on the outer surface of the case, when the airbag device is activated and the inflator generates hot gas, this gas causes the edge of the airbag. It does not hit the department directly. That is, the gas directly flows from the inside of the case to the back of the airbag. As a result, the heat load applied to the edge of the airbag is reduced.

[0010] The air bag device according to claim 2, airbag
A case with an opening through which the
A gas generating inflator attached to the
A gas inlet for receiving gas from the flatter,
The edge of the gas inlet is attached to the case,
The airbag stored inside and the opening of the case
The lid that covers it, and the projecting from the back surface of the lid,
For an airbag device that has a leg part for fixing the lid,
And the edge of the gas inlet of the airbag is the case
Is placed on the outer surface of the case around the opening of the
An airbag device fastened to an outer surface, wherein the airbag device further comprises a protrusion provided on a side surface of the case, and the protrusion with the opening of the case. A through-hole penetrating in the extending direction of the edge portion, a rod-shaped fastening member inserted into the through-hole, and a protrusion that is arranged along the side surface of the case and into which the protrusion is inserted. A lid connecting plate having an insertion opening and a hook for locking the lid, a hook engaging opening provided on the leg piece of the lid, the hook engaging opening, and the gas receiving portion of the airbag. A protrusion engaging port provided at an edge portion of the inlet, into which the protrusion is inserted, and the protrusion engaging port of the airbag and the protrusion inserting port of the lid connecting plate. Insert the stopper member into the through hole of the protrusion, and insert an air bag between the stopper member and the case. The airbag and the lid connecting plate are inserted so that the airbag and the lid connecting plate are inserted so that the lid and the lid connecting plate are connected to the case. It is characterized by being connected to a lid connecting plate.

In assembling this airbag device, when the folded airbag is stored in the case, the edge of the gas inlet of the airbag is provided along the outer surface of the side surface of the case. The projecting portion engaging port is engaged with the projecting portion on the side surface of the case. Next, the lid connecting plate is arranged along the outer surface of the side surface of the case, and the protrusion insertion port of the lid connecting plate is engaged with the protrusion.

After that, the retaining member is inserted into the rod-shaped member insertion hole of the protrusion. As a result, the airbag and the lid connecting plate are connected to the case.

Then, the lid is put on the case so as to cover the opening of the case, and the hook of the lid connecting plate is engaged with the hook engaging opening of the leg piece.

In such an airbag device, the airbag and the lid can be connected to the lid without using bolts or rivets.

According to a third aspect of the present invention, in the second aspect, the edge portion of the airbag has a first portion that extends along the outer surface of the case after wrapping around the opening of the case. And a second portion which is connected to the first portion, is folded back at the end side of the lid connecting plate, and extends along the outer surface of the lid connecting plate. And the projection engaging port is provided on both the second portion,
The projections are inserted into both of these projection engagement ports.

The airbag device according to a fourth aspect is the airbag device according to the second aspect, wherein the edge portion of the airbag extends around the opening of the case and then extends along the outer surface of the case. And a second portion that continues to the first portion, is folded back at the edge side of the lid connecting plate, and is along the outer surface of the lid connecting plate only near the edge side of the lid connecting plate, A third portion that continues to the second portion, enters a back surface from an outer surface of the lid connecting plate through a slit provided in the lid connecting plate, and further extends along the back surface; And the projection engaging ports are provided in both the first portion and the third portion, and the projections are inserted in both of the projecting engaging openings. is there.

In the airbag device according to the third and fourth aspects, since the protrusions are inserted into both of the protrusion engagement ports provided in the two edge portions of the airbag, the edge of the airbag is The mounting strength of the part to the case is extremely high.

According to the fourth aspect of the airbag device, the edge portion of the airbag extends along the outer surface of the lid connecting plate only near the edge. Therefore, when the fastening member is inserted into the through hole of the protrusion as in claim 5, the fastening member does not come into contact with the edge portion of the airbag, and the fastening member can be extremely easily fitted into the through hole of the protrusion. Can be inserted.

The airbag device according to claim 5 is the airbag device according to any one of claims 2 to 4, wherein a plurality of the protrusions are provided at intervals in the extending direction of the edge of the opening of the case. The through holes penetrating the protrusions on the same side surface of the case are arranged in a straight line, and one fastening member is inserted into the plurality of through holes arranged in the straight line. It is characterized by that.

In the airbag device according to the fifth aspect, after the protrusions are inserted into the protrusion engagement ports of the airbag and the protrusion insertion ports of the lid connecting plate, the through holes of the protrusions aligned in a straight line. The airbag and the lid connecting plate are attached to the case by sequentially passing one retaining member in a skewered manner on the above. Therefore, the operation of passing the fastening member through the through hole becomes extremely easy. Further, since one retaining member is inserted into the plurality of through holes, the retaining member is reliably prevented from coming out of the through hole.

The airbag device according to a sixth aspect is the airbag device according to any one of the second to fifth aspects, wherein the protrusion extends on a side surface of the case in a direction substantially perpendicular to an edge of the case opening. The slits are formed by providing two slits and projecting the space between the two slits to the outside of the case, and the slits are separated from the protruding portion in the direction toward and away from the case opening edge portion. It is characterized in that it extends in both directions.

In the airbag device according to the sixth aspect, the protrusion can be formed very easily. The space between the slits adjacent to the protrusion is deformed when an instrument panel impact is applied to the lid. Thereby, the instrument panel impact can be absorbed.

An air bag device according to a seventh aspect of the present invention is the airbag device according to the sixth aspect, wherein a portion of the case, which is closer to an edge of the case opening opening than the protrusion, is between two slits sandwiching the protrusion. The part is provided with an opening or a notch.

According to the seventh aspect of the invention, when the impact on the instrument panel is applied, the portion provided with the opening or the notch is stretched to absorb the impact on the instrument panel.

An airbag apparatus according to an eighth aspect is the airbag apparatus according to any one of the second to seventh aspects, wherein the lid connecting plate is
It is characterized in that a fragile portion is provided that is deformed when the edge portion of the protrusion insertion opening is pressed by the protrusion due to an instrument panel impact.

In the airbag device according to the eighth aspect, when the instrument panel impact is applied, the fragile portion is deformed, whereby the instrument panel impact is absorbed.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments will be described below with reference to the drawings. 1 is a perspective view of a passenger airbag device according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. 4 and FIG. 4 are exploded perspective views.

As shown in FIG. 3, the airbag apparatus for a passenger seat includes a folded airbag 10 and the airbag 1.
It is mainly composed of a metal case 12 for storing 0, a lid 16 for covering the opening 14 of the case 12, a gas generating inflator 18 for deploying the airbag 10, and lid connecting plates 20, 22. ing.

The case 12 is provided with an insertion opening 23 for the inflator 18 on its lateral side surface. In addition, at the edge of the opening 14 of the case 12, a protrusion 24 for attaching the airbag 10 and the lid connecting plates 20 and 22,
26 are provided. The protrusion 24 is arranged on the side surface of the case 12 in the longitudinal direction, and the protrusion 26 is arranged on the side surface of the case 12 in the lateral direction.

Each of the projections 24 and 26 is formed by forming two slits in the case 12 in a direction orthogonal to the edge of the opening 14 and knocking outward between the slits. .

The protrusions 24, 26 formed in this way
Has a through hole 2 penetrating in the extending direction of the edge of the opening 14.
8 and 30 are formed. The through holes 28, 28 ...
Are arranged in a straight line, and the through holes 30, 30 ... Are also arranged in a straight line.

The airbag 10 is provided with flaps 32 and 34 at the edge of the gas receiving port from the inflator 18, and the flap engaging ports (upper side) 3 are provided in each of the flaps 32 and 34.
6, 40 and projection engaging ports (lower side) 38, 42 are provided.

The lid connecting plates 20 and 22 are provided with projection insertion holes 44 and 46, and L-shaped hooks 48 and 50 are provided on the upper side of the drawing.

On the back surface of the lid 16, there are provided leg pieces 52 extending in the longitudinal direction and leg pieces 54 extending in the lateral direction. Each of the leg pieces 52, 54 has a hook 48, 5
Hook engagement ports 56 and 58 that engage with 0 are provided.

When assembling this passenger-side airbag device, the folded airbag 10 is stored in the case 12 with the inflator 18, and the flaps 32, 3 are provided.
4 is hung on the outer surface of the case 12. Then, after inserting the protrusions 24, 26 into the protrusion engagement ports (upper side) 36, 40, the lid connecting plates 20, 22 are overlapped with the flaps 32, 34, and the protrusions 24, 26 are inserted into the protrusion insertion ports 44, 46. Insert. Thereafter, the flaps 32 and 34 are folded back, and the protrusions 24 and 26 are inserted into the protrusion engagement ports (lower side) 38 and 40.

Next, the through holes 28 of the projections 24, 24 ...
The plate-shaped fastening member 62 is inserted into the projections 28, 26.
The plate-shaped fastening member 64 is inserted into the through holes 30, 30. Thereby, the airbag 10 and the lid connecting plate 2
0 and 22 are connected to the case 12.

Then, the lid 16 is put on the opening 14,
The hook engagement ports 56 and 58 are engaged with the hooks 48 and 50. As a result, the lid 16 is connected to the lid connecting plates 20, 22.
Connected to.

In this embodiment, the hook engaging ports 56,
The hooks 48, 50 are loosely fitted to the hook 58, and the hooks 48, 5 have play that allows the lid 16 to move slightly in the vertical direction in the drawing.
0 and the inner peripheral surfaces of the hook engaging openings 56 and 58.

In the passenger airbag device thus constructed, the case 12 is fixed to the vehicle body side strength member (not shown) in the instrument panel (not shown). Then, the lid 16 is locked to the opening (not shown) for installing the airbag device in the instrument panel. On this occasion,
The lid 16 is movable in the vertical direction in the figure, and the lid connecting plate 2
Since it is attached to No. 0 and 22, even if there is a slight error in the positional relationship between the case 12 and the instrument panel, the outer surface of the lid 16 and the outer surface of the instrument panel are exactly flush with each other. The device can be installed.

When a vehicle equipped with this air bag device collides, the inflator 18 operates to eject gas and the air bag 10 starts to deploy. When pushed by the airbag 10 to be deployed, the lid 16 is torn along the tear line (not shown), and the airbag 10 is deployed in the vehicle compartment. In this case, the flaps 32 and 34 of the airbag 10 are attached to the case 12
Since it is pulled out to the outer surface of the case 12 from the opening port 14 of the
The gas from the inflator 18 does not directly contact the flaps 32 and 34. For this reason, the temperature applied to the flaps 32, 34 becomes lower than in the conventional case, so that the heat resistance required for the base fabric of the airbag 10 is low, and the thickness of the base fabric can be small. . As a result,
The folded body of the airbag 10 can be made smaller than before, and the size of the airbag device can be reduced.

This passenger-side airbag device is assembled without hitting rivets or bolts at all, so that the labor required for manufacturing is reduced and the manufacturing cost is reduced.

FIGS. 5 to 10 and FIG. 15 show another example of the shape of the projection insertion opening provided in the lid connecting plates 20 and 22 (according to the aspect of claim 7 or 8). A fragile portion for absorbing an instrument panel impact is formed on the lid 16 side of each projection insertion port.

The projection insertion opening 44A in FIG. 5 and the projection insertion opening 44G in FIG. 15 are substantially trapezoidal and have a hypotenuse portion 44a which narrows upward. When the instrument panel impact is applied, the lid connecting plate 20A is pushed downward so that the protrusion 24 pushes the hypotenuse portion 44a open. The instrument panel impact is absorbed by the oblique side portion 44a being deformed so as to be pushed open. 5 (b) and 15 (b) are perspective views of the same parts as in FIGS. 5 (a) and 15 (a), respectively.

The projection insertion port 44B of the lid connecting plate 20B shown in FIG. 6 has a substantially trapezoidal shape, and a plurality of projections 4 are formed on the hypotenuse.
4b is provided. When an instrument panel impact is applied,
As the convex portion 44b bends, the upper portion of the protruding portion insertion port 44B is deformed so as to be pushed open by the protruding portion 24, and the instrument panel impact is absorbed.

The projecting portion insertion port 44C of the lid connecting plate 20C shown in FIG. 7 has a projecting portion 44c projecting from the side on the upper side of the projecting portion 24. The instrument panel impact is absorbed by the deformation of the convex portion 44c when the instrument panel impact is applied. 7 (b) is a perspective view of the same portion as FIG. 7 (a).

The protruding portion insertion port 44D of the lid connecting plate 20D shown in FIG. 8 has a tongue piece 44d that hangs from the upper side of the protruding portion 24. The instrument panel impact is absorbed by the deformation of the tongue piece 44d when the instrument panel impact is applied. 8 (b) is a sectional view taken along line BB of FIG. 8 (a).

The lid connecting plates 20E and 20 shown in FIGS.
The tongue pieces 44e, 44e, 44F of the F have a narrow width,
44f is provided. The tongue piece 44f is curved in a substantially S shape. The instrument panel impact is absorbed by the deformation of these tongue pieces 44e, 44f.

11 to 14 show an instrument panel impact absorbing mechanism provided in the vicinity of the protrusion 24 of the case 12.

In FIGS. 11 to 14, two slits 70 and 72 extending in the vertical direction are provided on both sides of the protrusion 24. The slits 70 and 72 are bidirectionally above and below the protrusion 24. Has been extended to.

In FIG. 12, a plurality of circular openings 74 are provided above the protrusion 24. In FIG. 13, the protrusion 24
On the upper side of the above, there is provided a single elongated oval opening 76 in the vertical direction. In FIG. 14, a notch 78 that cuts in from the slits 70 and 72 is provided above the protrusion 24.

When an instrument panel impact is applied to the case 12 shown in FIGS. 11 to 14, the upper side of the protrusion 24 between the slits 70 and 72 extends and the lower side of the protrusion 24 is deformed so as to buckle. The shock is absorbed. 12th
14 to 14, by providing the openings 74, 76 or the notches 78, the upper side of the protrusion 24 is easily extended and the instrument panel impact is sufficiently absorbed.

FIG. 16 is a perspective view of an air bag for a passenger seat according to an embodiment of the present invention, and FIG. 17 is a sectional view taken along the line XVII-XVII in FIG. 18 and 19 are exploded perspective views.

In the present embodiment, the lid connecting plate 2
Slits 90 and 92 are provided along the lower edges of 0 'and 22'. The flaps 32 and 34 are the lid connecting plate 2
The lid connecting plate 2 that goes around the lower ends of 0 'and 22'
The lid connecting plate 2 near the lower end side of 0 ', 22'
It is arranged on the front side of 0 ', 22'. Flaps 32, 34
Then, through the slits 90 and 92, the lid connecting plate 2
The lid connecting plate 2 is pulled into the back side of 0 ', 22'.
The upper protrusion engaging ports 36, 40 and the lower protrusion engaging ports 38, 42 face each other and extend upward in the drawing along the back surfaces of the 0 'and 22'. After the protrusion 24 passes through the protrusion engagement ports 36 and 38,
The protrusion 26 is inserted into the protrusion insertion port 44, and
After passing 0, 42, it is inserted into the projection insertion port 46. Fastening members 6 are respectively attached to the through holes 28 and 30 of the protrusions 24 and 26.
The lid connecting plate 2 is formed by inserting the second and the second 64.
0 ′ and 22 ′ are fixed to the case 12.

Other configurations of FIGS. 16 to 19 are the same as those of FIGS.
It is the same as the figure.

The passenger seat airbag device shown in FIGS. 16 to 19 has the same effects as those of the passenger seat airbag device shown in FIGS. In the passenger seat airbag device of FIGS. 16 to 19, the fastening member 6 is further provided.
The effect that it is easy to pass 2, 2 through the through holes 28, 30 is achieved.

That is, the flaps 32 and 34 are slits 9
It is drawn through the 0, 92 to the back side of the lid connecting plates 20 ′, 22 ′, and on the front side of the lid connecting plates 20 ′, 22 ′, on the side of the protrusion insertion ports 44, 46 (through Hole 2
The flaps 32 and 34 do not exist on the sides (8 and 30). Therefore, the fastening members 62 and 64 are connected to the through holes 28 and 30.
When passing through the flaps, the fastening members 62 and 64 are flaps 32 and 3.
It does not hit 4. As a result, the fastening members 62 and 64 can be easily passed through the through holes 28 and 30.

[0057]

As described above, in the airbag device of the present invention, the edges of the airbag do not come into direct contact with the gas from the inflator, and the heat resistance and thickness required for the airbag are reduced. You can Further, this makes it possible to reduce the bulk of the folded airbag body and downsize the airbag apparatus.

The airbag device according to claims 2 to 4 is easy to assemble and the assembly cost is low. In addition, the lid and the instrument panel can be easily and extremely accurately aligned in the same plane.

In the airbag device of the fifth aspect, the fastening member can be easily inserted into the through hole of the case, and the assembly of the airbag device becomes easier. Also, the fastening member is firmly held by the case.

In the airbag device according to the sixth and seventh aspects, the instrument panel impact can be absorbed by the deformation in the vicinity of the projecting portion of the case, and particularly according to the fourth aspect, the instrument panel impact can be sufficiently absorbed.

In the airbag device of the eighth aspect, the instrument panel impact can be absorbed by the deformation of the lid connecting plate.

[Brief description of drawings]

FIG. 1 is a perspective view showing an apparatus according to an embodiment.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is an exploded perspective view of the apparatus of the embodiment.

FIG. 4 is an exploded perspective view of the apparatus of the embodiment.

5A and 5B are a front view and a perspective view showing a protrusion insertion opening 44A.

FIG. 6 is a front view showing a protrusion insertion port 44B.

7A and 7B are a front view and a perspective view showing a protrusion insertion opening 44C.

FIG. 8 is a front view and a cross-sectional view showing a protrusion insertion port 44D.

FIG. 9 is a front view showing a protrusion insertion opening 44E.

FIG. 10 is a front view showing a protrusion insertion opening 44F.

FIG. 11 is a perspective view showing an instrument panel impact absorbing mechanism of the case.

FIG. 12 is a perspective view showing an instrument panel impact absorbing mechanism of the case.

FIG. 13 is a perspective view showing an instrument panel impact absorbing mechanism of the case.

FIG. 14 is a perspective view showing an instrument panel impact absorbing mechanism of the case.

15A and 15B are a front view and a perspective view showing a protrusion insertion opening 44G.

FIG. 16 is a perspective view showing an apparatus according to another embodiment.

17 is a sectional view taken along line XVII-XVII in FIG.

18 is an exploded perspective view of the apparatus of the embodiment shown in FIG.

19 is an exploded perspective view of the apparatus of the embodiment shown in FIG.

[Explanation of symbols]

10 Airbag 12 Case 14 Opening Port 16 Lid 18 Inflator 20, 20 ', 20A, 20B, 20C, 20D, 20
E, 20F, 22, 22 'Lid connecting plate 24, 26 Projection part 28, 30 Through hole 32, 34 Flap 36, 38, 40, 42 Projection part engagement port 44, 44A, 44B, 44C, 44D, 44E, 44
F, 44G, 46 Projection insertion opening 48, 50 Hook 52, 54 Leg piece 56, 58 Hook engagement opening 62, 64 Fastening member 70, 72 Slit 74, 76 Opening 78 Cut 90, 92 Slit

Continuation of the front page (56) Reference JP-A-7-69166 (JP, A) JP-A-7-69157 (JP, A) JP-A-6-24285 (JP, A) JP-A-5-294203 (JP , A) JP 4-356247 (JP, A) JP 4-50054 (JP, A) JP 7-69159 (JP, A) JP 7-32961 (JP, A) JP 6-298032 (JP, A) JP-A-52-77340 (JP, A) JP-A-8-58517 (JP, A) JP-A-6-1193 (JP, A) Actual Kaihei 7-15455 (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B60R 21/20

Claims (8)

(57) [Claims] 1. A case having an opening through which an airbag passes during deployment, a gas generating inflator attached to the case, and a gas receiving port for receiving gas from the inflator, the gas receiving port An edge portion of the air bag that is attached to the case, is housed in the case, a lid that covers the opening of the case, and a lid fixing leg piece that projects from the back surface of the lid. An edge portion of the gas receiving port of the airbag is arranged on an outer surface of the case so as to surround the opening of the case, and Lid connection that overlaps the edge
A plate is provided and the lid connecting plate has a hook for locking the lid.
And a hook engaging port provided on the lid leg piece and the hook.
Are engaged with each other to connect the lid to the lid connecting plate.
An airbag device characterized by: 2. An opening through which the airbag passes during deployment.
A case having the same, a gas generating inflator attached to the case, and a gas inlet for receiving gas from the inflator.
The edge of the gas inlet is attached to the case,
An airbag housed in the case, a lid covering the opening of the case , and a leg fixing portion protruding from the back surface of the lid for fixing the lid.
When, in the airbag apparatus having the edge of the gas introducing port of the air bag, the open of the case
Arranged on the outer surface of the case around the opening,
An airbag device that is fastened, wherein the airbag device further comprises a protrusion protruding from a side surface of the case, the protrusion extending from an edge of the opening of the case. A through-hole penetrating in the direction, a rod-shaped fastening member inserted in the through-hole, and a protrusion insertion port into which the protrusion is inserted, which is arranged along the side surface of the case, A lid connecting plate having a hook for locking the lid, a hook engaging port provided on the leg piece portion of the lid, and provided on an edge portion of the gas receiving port of the airbag. And a protrusion engaging port into which the protrusion is inserted, and the protrusion is inserted into the protrusion engaging port of the airbag and the protrusion inserting port of the lid connecting plate. The fastening member in the through hole of the portion, and an airbag between the fastening member and the case. And the lid connecting plate are inserted so that the airbag and the lid connecting plate are connected to the case, and the hook is engaged with the hook engaging port of the lid leg piece to attach the lid to the lid. An airbag device which is connected to a connecting plate. 3. The edge portion of the airbag according to claim 2, wherein the edge portion of the airbag extends around the opening of the case and then extends along an outer surface of the case; and the first portion. And a second portion that is folded back at the edge side of the lid connecting plate and extends along the outer surface of the lid connecting plate, and both of the first portion and the second portion are formed. An airbag device, wherein the projection engaging openings are provided in the projections, and the projections are inserted into both of the projection engaging openings. 4. The first portion according to claim 2, wherein the edge portion of the airbag has a first portion that extends along the outer surface of the case after wrapping around the opening of the case. And a second portion that is folded back at the edge side of the lid connecting plate and extends along the outer surface of the lid connecting plate only in the vicinity of the edge side of the lid connecting plate. A third part which extends from the outer surface of the lid connecting plate into the back surface through the slit provided in the lid connecting plate and further extends along the back surface.
And the projection engaging openings are provided in both the first and third portions, and the projection is inserted into both of these projection engaging openings. Airbag device that does. 5. The case according to claim 2, wherein a plurality of the protrusions are provided at intervals in the extending direction of the edge portion of the opening of the case, and are the same in the case. The through holes penetrating through the protrusions on the side surface are arranged in a straight line, and the one fastening member is inserted into the plurality of through holes arranged in the straight line. Airbag device. 6. The slit according to claim 2, wherein the protrusion has two slits formed on a side surface of the case and extending in a direction substantially perpendicular to an edge of the case opening.
The slits are formed by protruding the space between the two slits to the outside of the case, and the slits extend in both directions from the protrusion to the direction close to and away from the case opening edge. An airbag device characterized in that 7. The opening or notch according to claim 6, wherein a portion of the case that is closer to the edge of the case opening than the protrusion is between the two slits that sandwich the protrusion. An airbag device characterized by being provided with. 8. The fragile portion according to claim 2, wherein the lid connecting plate is provided with a fragile portion that is deformed when an edge portion of the protrusion insertion opening is pressed by the protrusion due to an instrument panel impact. An airbag device characterized by being provided.