JP5871424B2 - Cover body of airbag device - Google Patents

Description

  The present invention relates to a cover body of an airbag device that is deployed by the pressure with which the airbag is inflated when the airbag is inflated.

  2. Description of the Related Art Conventionally, an airbag device for a passenger in a passenger seat disposed on an instrument panel of an automobile is known. The airbag device includes a box-shaped case body, and a folded airbag and an inflator for injecting a gas for inflating the airbag are housed inside the case body. The upper opening is covered with a cover body of a seamless design that is formed integrally with the instrument panel, that is, seamlessly. In this cover body, a tear line which is a tearable tear such as a substantially plane H shape or a plane C shape is formed, and a portion surrounded by the tear line is partitioned and formed as a planned door portion. . The planned door portion is connected to an outer rim, which is an outer portion surrounding the planned door portion, via a hinge member having flexibility, that is, a hinge portion. When the automobile collides, the airbag into which the inflation gas is blown from the inflator pushes up the planned door portion covering the inflation side of the airbag, breaks the tear line by the inflation pressure, and the door flap, that is, the door portion It is comprised so that it may open (for example, refer patent document 1).

Japanese translation of PCT publication No. 2002-507172 (page 6-8, FIG. 3)

  However, since the airbag exerts a pushing force on the entire door portion, the pushing force also acts on the hinge portion. That is, the entire door portion tends to rise together with the hinge portion. Therefore, since a load is applied to the hinge portion, it is not easy to make the hinge portion flexible and supple when it can withstand this load. When the flexibility and flexibility of the hinge part are reduced, resistance is generated in the rotation (deployment) operation of the door part, the primary peak pressure of the airbag is increased, and the impact applied to the airbag and the cover body is not increased. In addition, it is necessary to adjust the pressure of the expansion gas or use an expensive member.

  Therefore, it is desired to make the deployment of the door portion more smoothly when the airbag is inflated.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a cover body of an airbag device that smoothly deploys a door portion when the airbag is inflated.

The cover body of the airbag device according to claim 1 is a cover body of the airbag device that covers the stored airbag and forms a door portion that is deployed by the inflation pressure of the airbag when the airbag is inflated. And an outer door planned portion having a first side portion and a second side portion opposite to each other, and a first fragile side portion and each second side corresponding to each first side portion. An outer member having a second fragile side portion facing the portion and having a frame-like fragile portion that defines an outer edge portion of the planned outer door portion, and a first opposing side portion and a facing portion. An inner door planned portion having a second opposing side portion and disposed on the airbag side of the outer door planned portion, an inner outer portion surrounding the inner door planned portion, and the first of the inner door planned portions. The opposite side portion and the inner shell portion are connected to one of the weak portions. The second weakened portion of the weakened portion so as to be able to break each of the second opposed side portions of the inner door planned portion and the inner shell portion. An inner member having a connecting portion connected along a side portion, and the inner door planned portion is a portion in which a portion excluding the hinge portion and the connecting portion is separated from the inner shell portion. is there.

  The cover body of the airbag device according to claim 2 is the cover body of the airbag device according to claim 1, wherein the connecting portion is separated from the other first opposing side portion of the inner door planned portion. Each of the second opposing side portions of the planned inner door portion and the inner outline portion are connected along the second fragile side portions of the fragile portion so as to be breakable.

According to the cover body of the airbag device according to claim 1, the first opposed side portion of the inner door planned portion of the inner member and the inner outer portion surrounding the inner door planned portion are the first of the weak portions. The bridging portion is connected by a hinge portion across the fragile side portion, and the second opposing side portion of the planned inner door portion and the inner shell portion are ruptureable along the second fragile side portion of the fragile portion. And the portion excluding the hinge portion and the connecting portion of the inner door planned portion is separated from the inner outer portion, so that the inflation pressure of the airbag is on the first fragile side portion side of the fragile portion. To restrain the expansion of the hinge part and the breakage of the first fragile side of one of the fragile parts to concentrate the inflation pressure of the airbag on the other first fragile side part of the fragile part The first fragile side portion of the fragile portion from the other first fragile side portion Sequentially smoothly cleaved to can be smoothly deployed.

  According to the cover body of the airbag device according to claim 2, in addition to the effect of the cover body of the airbag device according to claim 1, the connecting portion is separated from the other first opposing side portion of the inner door planned portion. By connecting each second opposing side portion of the planned inner door portion and the inner outline portion along the second fragile side portion of the fragile portion so as to be broken, A connecting line is formed on the first opposing side of the connecting portion to connect to the inner shell portion via the connecting portion, and the inflation pressure of the airbag is more reliably transferred to the other first fragile side of the fragile portion. The other first fragile side portions of the fragile portion can be more smoothly cleaved by being concentrated.

It is a perspective view which shows typically the initial stage deformation state by expansion | swelling of the airbag of the inner member of one Embodiment of the cover body of the airbag apparatus of this invention. It is explanatory drawing which shows the deployment behavior of an airbag apparatus same as the above from the side surface side. It is explanatory drawing which shows the deployment behavior of an airbag apparatus same as the above on the front side. It is a disassembled perspective view which shows a cover body same as the above. It is a perspective view which shows typically the initial deformation | transformation state by expansion | swelling of the airbag of a cover body at the time of expansion | deployment of an airbag same as the above. It is a perspective view which shows a part of vehicle body provided with the airbag apparatus same as the above.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  2, 3, 5, and 6, reference numeral 10 denotes an airbag device, and the airbag device 10 constitutes an airbag device 10 for a passenger in a passenger seat provided on an upper part of an instrument panel portion 13 of an automobile. To do. The instrument panel portion 13 is provided at the front portion of the passenger compartment over substantially the entire length in the vehicle width direction, and the front window glass 14 is positioned above the instrument panel portion 13. An airbag device 10 is installed inside the instrument panel portion 13 so as to face the passenger in the passenger seat. The airbag device 10 includes a case body 15 that is a member to be attached and is also referred to as a retainer, an inflator 16 that is disposed at the lower portion of the case body 15, and an airbag 17 that is folded and stored at the upper portion of the case body 15. And a cover body 18 that covers the airbag 17, that is, the opening 15 a at the top of the case body 15. In addition, a gas jet port 15b that communicates vertically is provided at the bottom (bottom) of the case body 15. Further, a hook 15c having a substantially C-shaped cross section is attached to the outer surface of the upper portion of the case body 15 as an attached portion. The inflator 16 is formed in, for example, a cylindrical shape, and various inflators 16 such as a combustion type (pyro type), a stored type that compresses and stores gas, and a hybrid type that combines these are used. In the airbag device 10, the case body 15 is attached to the vehicle body side member 20 via the bracket 19.

  When an automobile equipped with the airbag device 10 collides, the airbag 17 is inflated by the gas supplied from the inflator 16, the cover body 18 is broken by the inflation pressure, and the airbag 17 is expanded. The airbag 17 projects upward as a predetermined direction, and the airbag 17 is inflated and deployed forward of the occupant. Hereinafter, a predetermined direction on the bulging side of the airbag 17, that is, the occupant side, is upward (in the direction of arrow A shown in FIG. 2 and the like), the front side or the front side, and the opposite side of the bulging side is downward (FIG. 2 and the like). The direction of the arrow B shown in FIG. Further, the front-rear direction and the both-side direction in the state where the airbag device 10 is attached to the automobile will be described as the front-rear direction and the both-side direction. However, the attachment state of the airbag device 10 is not limited to this configuration. It can also be attached with the side facing upward or rearward on the rear side.

  The cover body 18 covers an outer member 21 that constitutes a so-called instrument panel, a reinforcing inner member 22 that is integrally attached to the back surface side of the outer member 21, and a front surface side of the outer member 21, for example. An interior member referred to as a so-called seamless lid or seamless instrument panel, which is formed integrally with an instrument panel portion 13 that is an automotive interior panel, is provided with a formed skin portion (not shown). The cover body 18 forms a door portion 24 that is an airbag inflating door as a door flap that is broken and deployed by the inflation of the airbag 17.

  The outer member 21 shown in FIGS. 2 to 6 is also called an outer, a skin panel, an outer panel, a panel body, a lid outer, and the like. For example, the outer member 21 is an injection molded product formed by injecting a predetermined synthetic resin into a mold. It is made of hard resin. The outer member 21 integrally covers the surface side of the instrument panel portion 13 and is exposed to the outside, and is provided in a substantially plate shape at a front portion of the vehicle compartment over substantially the entire length in the vehicle width direction.

  Further, on the back side of the outer member 21, a thin portion 25 is formed as a fragile portion so as to be substantially opposed to the opening 15a at the upper portion of the case body 15, and an outer edge portion is defined by the thin portion 25. The outer portion is a pair of front and rear outer door portions 26, 26, and the outer portion of the thin portion 25, that is, the portion surrounding the outer door portions 26, 26 is an outer outer portion 27 that is a non-deployment portion. ing.

  The thin portion 25 can also be called a tear line, a tear, a tear groove, a planned fracture portion, a planned fracture groove, a planned door line portion or a fracture portion, and is more fragile than the planned outer door portion 26 and the outer outer portion 27. In this embodiment, it is a weak part that can be broken and easily deformed. In this embodiment, the hinge edge is planned as a hinge edge thin part that is one long side as one first fragile side part that extends to both sides of the front and rear ends. Portions 25a, 25a, a free edge predetermined portion 25b which is another long side as the other first fragile side portion extending in both sides substantially parallel to the hinge edge predetermined portions 25a, 25a, and these hinge edges An outline that is a short side as a second fragile side that extends between the opposite sides of the planned portions 25a, 25a and the free edge planned portion 25b and forms a shorter pair than the planned portions 25a, 25b. In the shape of a substantially "day" with side tear planned portions 25c, 25c, 25c, 25c as tear lines, It If has a configuration that combines a square frame-shaped tear line is a closed loop. The thin-walled portion 25 is formed by the shape of the mold cavity during injection molding, and is a so-called tear center at the approximate center of each planned portion 25a, 25b, 25c due to a triangular cross-sectional groove opening downward in an obtuse angle. The portion is a planned fracture line 28 that is the thinnest portion with the smallest thickness dimension. The thin-walled portion 25 is preferably broken along the planned fracture line 28, which is the desired fracture position.

  Each of the planned outer door portions 26 covers a bulging side of the airbag 17 that is normally folded and stored, and is a portion that constitutes the door portion 24 when the airbag 17 is bulged. In the shape of a plane quadrangle (rectangle) having long side portions 26a and 26a as side portions and short side portions 26b and 26b as opposing second sides shorter than these long side portions 26a and 26a Is formed. Each outer door planned portion 26 has an outer edge portion defined by a hinge edge planned portion 25a, a free edge planned portion 25b, and side side planned cleavage portions 25c and 25c. That is, the hinge edge planned portion 25a corresponds to one long side portion 26a, the free edge planned portion 25b corresponds to the other long side portion 26a, and each side portion is cleaved to each short side portion 26b. The planned part 25c corresponds.

  Further, a positioning convex portion 31 for positioning the inner member 22 is projected from the outer shell portion 27. A plurality of locking projections 33 for locking the outer member 21 to the instrument panel portion 13 via clips 32 or the like as locking members are provided in the vicinity of the outer edge portion of the outer shell portion 27. ing.

  On the other hand, as shown in FIGS. 1 to 5, the inner member 22 is also called an inner member, a backing member, a backing member, or a lid inner member, and is formed of a softer material than the material constituting the outer member 21. It is made of a soft resin and is joined to the outer member 21 at the inside and outside of the thin portion 25.

  The inner member 22 is fixed to the back surface side of the outer outer portion 27 of the outer member 21 to form a rectangular plate frame-shaped inner outer portion 36 that forms the outer portion C. A rectangular cylindrical mounting piece 37 projecting downward from the end on the peripheral side, located on the inner peripheral side of the inner shell 36 and fixed to the back side of each outer door planned portion 26, 26 to be a door plan Inner door planned portions 38, 38 forming part D, a plurality of, for example, five hinge portions 39 and a plurality of, for example, a pair of connecting portions 40, for connecting these inner door planned portions 38, 38 to the inner shell portion 36 are provided. It is integrally formed. The inner shell portion 36 and the inner door planned portions 38, 38 are formed substantially flush, that is, on the same plane. Further, the inner member 22 has outer peripheries of the inner door planned portions 38, 38 except for the hinge portion 39 and the connecting portion 40 along the positions facing the respective side portion planned cleavage portion 25c and the free edge planned portion 25b of the thin portion 25. The portion is separated by a groove-shaped groove 41 having a small width.

  A positioning hole 43 for positioning the inner member 22 with respect to the outer member 21 by inserting the positioning convex portion 31 of the outer member 21 is formed in the inner shell portion 36.

  Further, the mounting piece portion 37 can also be called a standing wall or a retainer mounting vertical wall, and the hinge edge planned portions 25a, 25a and the side portion planned cleavage portions 25c, 25c, 25c of the thin portion 25 of the outer member 21, A rectangular cylinder is formed along the outside of 25c. The surface portions 37a and 37a facing the front and rear of the mounting piece 37 are formed with a plurality of mounting holes 37b, which are mounting portions and square square holes, and the mounting body 37b has a case body. A hook 15c provided on 15 is locked, and the cover body 18 and the case body 15 are connected.

  Also, each inner door planned portion 38 is a portion that covers the bulging side of the airbag 17 that is normally folded and stored, and constitutes the door portion 24 together with each outer door planned portion 26 when the airbag 17 is bulged. The hinge connecting part 38a and the discontinuous part 38b as first opposing side parts facing each other, and the reinforcing side edge part as the second opposing side part shorter than the hinge connecting part 38a and the discontinuous part 38b It is formed in a plane quadrangle (rectangular) shape including 38c and 38c. These inner door planned portions 38 are disposed on the back side of the outer door planned portion 26, and are door reinforcing portions that reinforce the outer door planned portion 26.

  Furthermore, each hinge part 39 connects the outer shell part C and the planned door part D in a deformable manner, and in the present embodiment, the hinge parts 39 face the hinge edge planned parts 25a, 25a which are the front and rear thin parts 25. Along the part, it curves downward (in the direction of arrow B shown in FIG. 2), that is, in the direction of the stored airbag 17 and straddles the hinge edge planned portions 25a, 25a, and the inner shell portion 36 and each inner door Each of the planned portions 38 is flexibly coupled to the hinge connecting portion 38a. In this way, the hinge part 39 is formed to be spaced downward from the thin part 25 so that the door part 24 can be easily and smoothly rotated even at low temperatures.

  Further, each connecting portion 40 connects the outer shell portion C and the planned door portion D in a deformable manner, and in this embodiment, the side portion to be split 25c, 25c, 25c, which are the thin portions 25 on both sides. 25c, 25c, 25c, 25c, 25c, 25c, 25c, 25c, 25c, 25c, 25c, 25c, 25c, 25c, and 25c. Are flexibly connected. Further, the connecting portions 40 and 40 corresponding to the respective inner door planned portions 38 are arranged at positions symmetrical to each other in the longitudinal direction of the inner door planned portion 38 which is the both-side direction, and each inner door scheduled in the front-rear direction. The portion 38 is disposed at a substantially central portion in the short direction, that is, at an intermediate position between each of the side cleavage scheduled portions 25c and 25c. That is, these connecting portions 40 are located at a predetermined distance from the free edge planned portion 25b of the outer member 21, that is, the discontinuous portion 38b of the inner door planned portion 38. Further, these connecting portions 40 are arranged on the sides of the roots of the hinge portions 39 located on both sides. Therefore, by the connecting portions 40, 40, one side surface portion 37c of the mounting piece portion 37, the inner outer portion 36, the connecting portion 40, the vicinity of the hinge connecting portion 38a of the inner door planned portion 38, the connecting portion 40, the inner outer portion 36 and A continuous connection line L is formed across the other side surface portion 37c of the attachment piece portion 37. Furthermore, groove-shaped cut portions 40a that set the breaking characteristics of the respective connecting portions 40 are formed below the connecting portions 40, that is, on the side of the stored airbag 17. The cut portion 40a is formed in a triangular cross section that opens downward.

  The skin portion covers the surface side of the outer member 21 to improve the appearance and feel, and is made of a soft resin. The skin portion is integrally insert-molded with respect to a member obtained by joining the outer member 21 and the inner member 22, for example. The skin portion may be omitted depending on the material of the outer member 21 and the like.

  Then, from the state shown in FIG. 6, the airbag device 10 is operated as shown in FIGS. 2 and 3, and when the inflation gas flows into the airbag 17 and inflates, that is, inflates and deploys, the airbag 17 is moved to the case body 15. The expansion pressure which expands in the inside presses the inner door planned portions 38 and 38 before and after the inner member 22, and pushes up the outer door planned portions 26 and 26 before and after the outer member 21 through the inner door planned portions 38 and 38. As a result, the inflation pressure of the airbag 17 acts on the thin-walled portion 25, and when the airbag 17 rises to reach the primary peak pressure, it has a sloped bulge shape that bulges gradually from both sides to the central portion. Let it form.

  That is, the movement of the planned door portion D (outer door planned portions 26, 26 and inner door planned portions 38, 38) and the outer portion C (outer outer portion 27 and inner outer portion 36) is caused by the connecting portions 40, 40, 40, 40, the extension of the hinge edge portions 25a, 25a and breakage due to shearing are suppressed, and the action of the inflation pressure of the airbag 17 on the free edge expected portion 25b is promoted. In other words, the side cleavage scheduled portions 25c, 25c, 25c, 25c are reinforced side edge portions 38c, 38c, 38c, 38c of the inner door planned portions 38, 38 of the inner member 22 by the connecting portions 40, 40, 40, 40. Are connected to the inner shell 36 by connecting the hinge connecting portions 38a, 38a of the inner door planned portions 38, 38 of the inner member 22 to the inner shell 36 by the hinge portions 39. Since the connected state is maintained, the lateral movement of the planned door portion D (the planned outer door portions 26 and 26 and the planned inner door portions 38 and 38), that is, the forward and backward movement is restricted and stopped. Deformation and elongation and breakage of the hinge edge planned portions 25a, 25a are delayed, and the upward movement of the planned door portion D (the planned outer door portions 26, 26 and the planned inner door portions 38, 38) is prevented. As a result, cleavage of the free edge planned portion 25b is promoted.

  As a result, first, the free edge planned portion 25b is cleaved and connected along the connecting line L, that is, an airbag chute 45 is formed in which the opening amount gradually increases from both side portions to the central portion (see FIG. 1 and FIG. 1). FIG. 5). And by the effect | action of this airbag chute 45, the rotational force for making the door planned part D incline large smoothly is obtained.

  Thereafter, the connecting portions 40, 40, 40, 40 are broken, that is, the thin portion 25, which is a weak portion of the outer member 21, is broken over the entire length, and the outer door planned portion 26 is separated from the other portions of the outer member 21. As shown by the imaginary lines in FIG. 2, the outer door planned portions 26 and 26 are rotated or expanded as the door portion 24 together with the inner door planned portions 38 and 38 around the hinge portions 39. The airbag 17 is inflated.

  Thus, according to the present embodiment, the hinge connecting portion 38a of the inner door planned portion 38 of the inner member 22 and the inner outer portion 36 are connected by the hinge portion 39 across the hinge edge planned portion 25a of the thin portion 25. At the same time, the reinforcing side edge portions 38c, 38c of the inner door planned portion 38 and the inner shell portion 36 are connected by connecting portions 40, 40 along the side portion planned cleavage portions 25c, 25c of the thin portion 25 so that they can be broken. This suppresses the expansion pressure of the airbag 17 from being applied to the hinge edge planned portion 25a side of the thin portion 25, thereby delaying the elongation deformation of the hinge portion 39 and the breakage of the hinge edge planned portion 25a of the thin portion 25. The inflation pressure of the airbag 17 can be concentrated on the 25 free edge planned portion 25b side, and the door portion 24 is sequentially and smoothly opened from the free edge planned portion 25b side of the thin portion 25 to the hinge edge planned portion 25a side. Can be deployed smoothly.

  Therefore, since the load applied to the hinge portion 39 can be suppressed, the hinge portion 39 can be made a flexible and supple member, so that the resistance of the rotation (deployment) operation of the door portion 24 hardly occurs, and the primary of the airbag 17 An increase in peak pressure can be suppressed, and an impact applied to the airbag 17 and the planned door portion D (the planned outer door portions 26 and 26 and the planned inner door portions 38 and 38) can be suppressed.

  And the entire door part 24 suppresses the bulging movement phenomenon in which the airbag 17 bulges and moves upward, and suppresses the internal pressure peak immediately before the airbag 17 opens the door part 24, The airbag 17 can be smoothly (mildly) deployed as a whole from the start of the airbag device 10 to the entire deployment of the airbag 17.

  Further, the thinned portion 25 is formed so that the reinforcing side edge portions 38c, 38c of the planned inner door portion 38 and the inner shell portion 36 can be broken at a position where the connecting portion 40 is separated from the discontinuous portion 38b of the planned inner door portion 38. By connecting along the respective side portion planned cleavage portions 25c, 25c, a connecting line L can be formed on the hinge connecting portion 38a side of the inner door planned portion 38 to be connected to the inner shell portion 36 via the connecting portion 40. . Therefore, the expansion pressure of the airbag 17 is more reliably concentrated to the free edge planned portion 25b side of the thin portion 25 that is off the connection line L, and the free edge planned portion 25b of the thin portion 25 is deformed and raised. Can be more reliably generated, and the free edge planned portion 25b can be more smoothly cleaved.

  In the above-described embodiment, the outer member 21 includes a pair of planned outer door portions 26, the inner member 22 includes a pair of planned inner door portions 38, and a so-called double flap that unfolds the door portion 24 back and forth. However, the present invention is not limited to this configuration. For example, the outer member 21 includes one planned outer door portion 26, the inner member 22 includes one planned inner door portion 38, and, for example, the door portion 24 faces forward. It can also be set as the structure of what is called a single flap to expand | deploy.

  Further, the thin portion 25, the outer door planned portion 26, and the inner door planned portion 38 are not limited to a square shape, but may be a polygonal shape having side portions that are opposed to each other. It can correspond to.

  Furthermore, in the above-described embodiment, the cover body 18 of the airbag device 10 for the passenger on the passenger seat of the instrument panel unit 13 has been described. However, the present invention is not limited to this configuration. For example, an instrument panel as an interior panel of an automobile The present invention can also be applied to a cover body of an airbag device installed in a place other than the portion 13.

  The present invention can be applied to a cover body of an airbag device for a passenger in a passenger seat of an automobile.

10 Airbag device
17 airbag
18 Cover body
21 Outer member
22 Inner material
24 Door
25 Thin-walled parts as vulnerable parts
25a Expected hinge edge as the first weak side
25b Free margin planned part as the first weak side
25c Side cleavage planned part as second weak side
26 Outer door planned part
26a Long side as first side
26b Short side as second side
36 Inner shell
38 Planned inner door
38a Hinge connection as first opposing side
38b Discontinuous part as first opposing side
38c Reinforced side edge as second opposing side
39 Hinge
40 connection

Claims (2)

A cover body of an airbag device that covers a stored airbag and forms a door portion that is deployed by the inflation pressure of the airbag when the airbag is inflated,
An outer door planned portion having a first side portion facing each other and a second side portion facing each other, a first fragile side portion corresponding to each first side portion, and each second side portion An outer member having a second fragile side portion facing and having a frame-like fragile portion defining an outer edge portion of the planned outer door portion;
An inner door planned portion having a first opposed side portion and a second opposed side portion opposed to each other and disposed on the airbag side of the planned outer door portion, and an inner shell surrounding the planned inner door portion A hinge portion that connects the first opposing side portion of one of the planned inner door portions and the inner shell portion across the first fragile side portion of the fragile portion, and the planned inner door portion An inner member having a connecting portion that connects each of the second opposing side portions of the portion and the inner shell portion along the second fragile side portions of the fragile portion so as to be breakable. ,
The cover part of the airbag apparatus , wherein the planned inner door part is separated from the inner shell part except for the hinge part and the connecting part . The connecting portion is formed at a position spaced from the other first opposing side portion of the inner door planned portion so that each of the second opposing side portions of the planned inner door portion and the inner shell portion can be broken. The cover body of the airbag apparatus according to claim 1, wherein the cover body is connected along each second weak side.

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