JP4842854B2 - Cover body of airbag device - Google Patents

Description

  The present invention relates to a cover body of an airbag device that covers a stored airbag.

  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 apparatus includes a box-shaped case body, and a folded airbag and an inflator for injecting gas for inflating the airbag are housed inside the case body. The upper opening of the body is covered by a cover body that is attached along the instrument panel. The cover body is formed with a tearable tear line such as a substantially plane H shape or a plane C shape, and a portion surrounded by the tear line is defined as a planned door portion. When the automobile collides, the airbag is inflated by injecting gas from the inflator, the tear line is broken by the inflation pressure of the airbag to form the door portion, and the portion where the tear line is not formed The door is expanded as a hinge to form a protruding opening, and the airbag is inflated from the protruding opening to alleviate the impact applied to the occupant.

For example, for a cover body of an airbag device provided in an instrument panel, a configuration is known in which the tear line is broken into a desired shape by arranging the tear line so as to substantially match the direction of the shearing force (for example, (See Patent Document 1).
JP 2004-1709 A

  By breaking such a cover body from a desired position of the tear line, for example, from the center part of the tear line, it becomes easy to smoothly deploy the door part and further smoothly inflate the airbag.

  However, when the door part of the cover body is difficult to deform, so to speak, if the door part is a rigid body, the behavior is such that the entire length of the tear line located in the center part is simultaneously broken, and the behavior of the door part is difficult to control. Have a problem.

  In particular, for the so-called seamless instrument panel that has a cover body that is formed integrally with the instrument panel in order to improve the appearance, etc., a separate part that is provided with a hinge part is joined to the back side of the planned door part of the instrument panel. For this reason, there is a problem that the planned door portion of the cover body is difficult to deform, and the tear line breaking behavior is difficult to control.

This invention is made in view of such a point, and it aims at providing the cover body of the airbag apparatus which can fracture | rupture a door planned line part from a desired position and can control the behavior of a cover body easily. .

The cover body of the airbag device according to claim 1 is at least partly due to a planned door portion disposed on the side of the airbag to be inflated, an outer portion surrounding the planned door portion, and a pressure when the airbag is inflated. There a door will line portion forming a deployable door portion broken away, covers the protruding side of the housing has been the airbag, the spout of the air bag when swelling of the airbag projects A cover body of an airbag device to be formed, comprising an outer door planned portion arranged on the bulging side of the airbag, an outer outer portion surrounding the outer door planned portion, and an outer door line portion , An inner door planned portion joined to the outer door planned portion to constitute the door planned portion, an inner outer portion joined to the outer outer portion to constitute the outer portion, the inner door planned portion and the inner outer portion Hinge part for connecting ; And a inner portion having a deformable wire portion, the door will wire section, in the break line portion fracture start position is set with eclipsed set to a line shape extending on both sides positioned outer door scheduled portion A central tear line, and a side tear line that extends from the center tear line to the front and rear sides of the door portion and the outer portion, and the deformation line portion is the inner door schedule. The inner portion is recessed and provided so that it can be easily deformed from the adjacent portion of the planned door portion , crossing the middle position of the central tear line, and back and forth from the position of the central tear line. it is those that have been extended to.

In this configuration, when the airbag is inflated, due to the pressure of the inflation, the planned door line portion including the central tear line arranged in the planned door portion is broken to form a protruding port of the airbag. Because it has a deformed line part that extends across the middle position of the central tear line and easily deforms from the adjacent part of the planned door part, the planned door part is easily deformed, and the door is scheduled at the early stage of airbag expansion The desired position of the part is greatly deformed, and the planned door line part can be easily broken from the desired position. Further, since the deformed line portion is provided in the planned inner door portion, the planned door portion can be deformed even if the planned outer door portion and the inner door planned portion are joined to form the planned door portion. It becomes easy to break from a desired position.
Cover of an airbag device according to claim 2, wherein, in the cover of the airbag apparatus according to claim 1, deformation line portions are those which are arranged symmetrically around the fracture starting point.

In this configuration, since the deformation line portion is arranged symmetrically around the break start position of the central tear line, when the airbag is inflated, the expected door portion is deformed around the break start position by the pressure of the inflation. In addition, it becomes easy to break the center tear line from the break starting position.

Cover of an airbag device according to claim 3, wherein, in the cover of the airbag apparatus according to claim 1 or 2, wherein the door portion to be the outer Guo portion and a plurality of hinge portions deformable for coupling the door portion And a plurality of deformation line portions arranged between the hinge portions along the unfolding direction.

In this configuration, when the airbag is inflated, the central tear line arranged in the planned door portion is broken by the pressure of the inflation, and then, part or all of the planned door line portion is broken and the door is broken. Part or all of the planned portion is cut off from the outer portion to form a door portion, and the door portion rotates with a hinge portion or the like as a fulcrum to form a protruding port of the airbag. Since the deformation line portion is disposed between the hinge portions along the direction in which the door portion is expanded, the deformation line portion is configured without affecting the formation and deformation operation of the hinge portion .

According to the cover body of the airbag device of the present invention, since the deformation line portion that easily deforms is provided, the deformation of the planned door portion can be easily controlled. Therefore, the planned door portion is broken from a desired position, the behavior of the cover body can be easily controlled, and the deployment characteristics of the airbag can be easily improved.

  Hereinafter, an embodiment of a cover body of an airbag device of the present invention will be described with reference to the drawings.

  In FIG. 3, reference numeral 1 denotes an airbag device. The airbag device 1 can also be called a passenger seat airbag module, and is an airbag device for a passenger on a passenger seat provided in an instrument panel portion of an automobile as a vehicle. 1 is constituted. And the instrument panel part is provided over the substantially full length of the vehicle width direction in the front part of the vehicle interior, and the front window glass is located above this instrument panel part. And in this instrument panel part, the airbag apparatus 1 is installed facing the passenger | crew of a passenger seat. The airbag device 1 includes a case body 4 that is a member to be attached, an inflator (not shown) housed in a lower portion of the case body 4, and a bag-like airbag that is folded and housed in the upper portion of the case body 4. 6 and a cover body 11 covering the opening at the top of the case body 4. The airbag device 1 is attached to the vehicle body by fixing the case body 4 to a member on the vehicle body side via a bracket (not shown). Further, the upper portion and the lower portion of the case body 4 are partitioned by a mid retainer (not shown) provided with a gas jet port communicating vertically, and the airbag 6 is accommodated above the mid retainer, and the mid retainer A cylindrical inflator is housed on the lower side. Furthermore, hooks having a substantially C-shaped cross section are attached to the front and rear surfaces of the upper portion of the case body 4 as attached portions. The inflator can take various shapes and methods, for example, in addition to a cylinder, it may be a disk, a combustion type (pyro type), a stored type that compresses and stores gas, or these Various inflators such as a hybrid type combining the above are used. In addition, 6a shown in FIG. 3 is a breakable cloth body that holds the folded shape of the airbag 6.

  When an automobile equipped with the airbag device 1 is impacted by a collision or the like, the airbag 6 is inflated by the gas supplied from the inflator, and the cover body 11 is broken by the inflating pressure. 5 is formed, the airbag 6 projects toward the upper side A as a predetermined direction on the bulging side, and is inflated and deployed forward of the occupant. In the following description, the predetermined direction on the bulging side of the airbag 6 is defined as the upper side A or the front side, and the opposite side of the bulging side is defined as the lower side or the back side. Further, the front-rear direction and the both-side direction that are the vehicle width direction in the state where the airbag apparatus 1 is attached to the automobile will be described as the front-rear direction and the both-side direction. F direction), the occupant side is the rear (arrow B direction shown in FIG. 2), but is not limited to this configuration. For example, the airbag device 1 is attached to the vehicle body with the bulging side facing upward or rearward on the rear side. You can also

  The cover body 11 is also called a lid or the like, and is attached to the outer part 21 constituting a so-called instrument panel and vibration welding or the like on the back side of the outer part 21 as shown in FIGS. The inner part 22 and a so-called seamless lid or a member called a seamless instrument panel which are integrally formed in the instrument panel part.

  The outer portion 21 integrally covers the surface side of the instrument panel portion and is exposed to the outside, that is, an instrument panel provided in a substantially plate shape at a front portion of the passenger compartment over substantially the entire length in the vehicle width direction. Part of the part. The outer portion 21 is made of resin, for example, an injection-molded product made of polypropylene resin, so to speak, is formed of a hard resin, and is attached to the vehicle body using a mounting tool such as a clip or a screw (not shown).

  Further, a tear line 24 that is a weak portion as a planned door line portion is formed on the back surface side of the outer portion 21 so as to be substantially opposed to the opening of the upper portion of the case body 4, and the outer outline portion that is a non-deployed portion. 25 and a pair of front and rear planer rectangular outer door portions 26 and 26 surrounded by the outer shell portion 25 are partitioned. The planned outer door portions 26, 26 cover the bulging side of the airbag 6 that is folded and stored in a normal state. The tear line 24 is a weak part that can be broken and easily deformed, and in the present embodiment, the tear line 24 has a central tear line 24a as a broken line part that extends the central part on both sides, and an outer tear line 24b that constitutes the outer shell. The shape is substantially “Sun” and is a combination of a closed-loop square frame-shaped tear line. A central portion in the longitudinal direction of the central tear line 24a is a fracture start position 27 that faces the central portion of the folded airbag. Further, the outer tear line 24b includes a side tear line 24c extending forward and backward continuously from the central tear line 24a, a front tear line 24d that connects end portions of the side tear lines 24c on the windshield side, and these side tear lines. A rear tear line 24e is provided for connecting the occupant side ends of the line 24c. The tear line 24 is formed as a thin-walled portion by a concave groove which is a cutting groove which is engraved with a rotary blade such as a milling blade on a flat portion formed flat by injection molding after the outer portion 21 is molded. However, the tear line 24 can also be formed as a concave groove during injection molding.

  On the other hand, the inner part 22 is made of a soft resin made of a softer material than the material constituting the outer part 21, and has a larger planar shape than the combined shape of the pair of planned outer door parts 26, 26. The outer line 21b is positioned on the inner side and the outer side of the outer tear line 24b and welded to the outer part 21, that is, coupled to the back surface of the outer door planned part 26 of the outer part 21 to form the planned door part C. An outer shell portion D is formed by being coupled to the outer outer shell portion 25 around the planned door portion 26. The inner portion 22 is formed of an elastomer resin, and is, for example, an injection molded product of TPO resin (thermoplastic olefin).

  As shown in FIGS. 1 to 9, the inner portion 22 includes a square plate frame-like inner outer portion 31 fixed to the back surface side of the outer outer portion 25 of the outer portion 21, and the inner outer portion 31. A rectangular tube-shaped mounting piece 32 projecting downward from the inner peripheral end and an inner peripheral portion 31 of the inner outer peripheral portion 31 and fixed to the back side of each outer door planned portion 26, 26 A rectangular plate-shaped inner door planned portion 33, 33 and a plurality of the inner door planned portion 33, 33 connected to the inner outer portion 31, a total of five pairs of ten hinge portions 34 in this embodiment are integrally formed. Has been.

  Further, as shown in FIG. 9, a plurality of welding ribs 36 are formed in a lattice shape on the joint surface, that is, the upper surface of the inner shell portion 31 and each inner door planned portion 33, and vibration welding using a vibration welding machine is used. These welding ribs 36 are melted, the inner shell 31 is welded and joined to the outer shell 25, and the inner door planned portions 33 and 33 are welded and joined to the outer door planned portions 26 and 26.

  Then, along the outer door planned portions 26, 26 and along the short side portions at both ends of each of the outer door planned portions 26, 26, the inner rupture portion having a substantially flat H shape and a small groove width. A certain cut portion 38 is formed, and the inner outer portion 31 and the planned inner door portions 33, 33 are partitioned, and one side of each inner door planned portion 33, 33 is respectively connected to the inner outer portion 31 by the hinge portion 34. It is connected. That is, the cutting portion 38 is formed along a central cutting line portion 38a along a position facing the central tear line 24a, and a position continuous with both ends of the central cutting line portion 38a and facing the side tear line 24c of the outer tear line 24b. And a side cutting line portion 38b.

  And each hinge part 34 connects the outer shell part D and the door plan part C so that a deformation | transformation is possible, and along the site | part which opposes some tear lines 24, in this Embodiment, the front-rear tear line The inner shell portion 31 and the inner door planned portion 33 are flexibly connected so as to straddle these tear lines 24 along the portions facing 24d and 24e. And this hinge part 34 is formed in the position which cut each inner door planned part 33, one end part is connected to the position separated from edge part 33a outside the inner door planned part 33, and the other end part is It is connected to the corner of the end portion of the inner shell 31 and is a connecting portion having a substantially U-shaped cross section that bulges downward, that is, toward the side of the stored airbag 6.

  Furthermore, each inner door planned portion 33 is formed with a deformed line portion 39 that is a linear weak portion that facilitates deformation of each inner door planned portion 33. In the present embodiment, the deformed line portion 39 is formed as a thin-walled portion by four rows of straight concave grooves in which the back surface side that is the airbag 6 side of each inner door planned portion 33 is recessed. Each deformation line part 39 intersects the central cutting line part 38a of the cutting part 38, is further arranged orthogonally and parallel to each other, and is located between the hinge parts 34 and is located at the outer end of the inner door planned part 33. It reaches the edge 33a. Each deformation line portion 39 is symmetrical with respect to the break start position 27 of the central cutting line portion 38a, which is the center of the cover body 11, so that in this embodiment, the deformation line portion 39 is rotationally symmetric with respect to the break start position 27 It is formed symmetrically with respect to a line (line E shown in FIG. 5) passing through the fracture start position 27 and orthogonal to the central cutting line portion 38a. Further, as shown in FIG. 4, the cross-sectional shape of the groove of each deformation line portion 39 is substantially V-shaped, and further, the corner portion 39a on the back surface side that is the airbag 6 side and the apex portion on the upper end that is the back side 39b has a smooth curved surface, and the airbag 6 is protected. Further, the resin thickness dimension t of the inner portion 22 of each deformation line portion 39 is set to 0.5 mm or more.

  Further, the mounting piece 32 of the inner portion 22 is formed in a square cylinder shape along the outer periphery of the outer tear line 24b of the outer portion 21, that is, along the protruding port 12. A plurality of mounting holes 42, each of which is a mounting portion and a square hole, are formed on the front and rear surfaces of the mounting piece 32, which are opposed to the front and rear, and are provided in the case body 4 in the mounting holes 42. The hooks are respectively locked, and the cover body 11 and the case body 4 are connected. Further, a plurality of reinforcing ribs 44 are integrally formed on the outer peripheral portion of the mounting piece portion 32 so as to integrally connect the upper portion of the mounting piece portion 32 and the lower surface of the inner outer portion 31, and the inner outer portion 31 and the mounting piece portion 32. The inner shell 31 is made as rigid as possible.

  Further, projecting piece portions 46 are extended from two locations in front of the inner shell portion 31 of the inner portion 22, and a substantially H-shaped alignment portion 47 is provided on each projecting piece portion 46. And the inner part 22 and the outer part 21 are aligned by inserting the positioning part which is not shown in figure which protruded in two places of the lower surface of the outer outer part 25 of the outer part 21 in these alignment parts 47. .

  Next, the deployment behavior of the cover body 11 when the airbag device 1 is activated will be described.

  When gas is supplied to the airbag 6 from the state shown in FIG. 1, the airbag 6 is inflated and expanded, that is, inflated in the case body 4, and the inner door planned portions 33 before and after the inner portion 22 are caused by the pressure of the inflation. 33 is pressed and deformed, and the planned outer door portions 26 and 26 before and after the outer portion 21 are pushed up through the planned inner door portions 33 and 33. Then, as shown in FIG. 5, the tear line 24 of the outer portion 21 is broken by this force, and the planned door portion C is rotated or developed as the door portion G by the hinge portion 34, so that the airbag 6 is inflated. Protrusions 12 are formed.

  Here, the deformed line portions 39 are formed in the planned inner door portions 33 and 33, and these deformed line portions 39 are formed symmetrically around the break start position 27 facing the substantially central portion of the airbag 6. Therefore, at the initial stage when the gas is introduced, the cover body 11 is deformed so as to rise around the break start position 27, and the tear line 24 is moved from the break start position 27 of the central tear line 24a as shown in FIG. After breaking, the breakage progresses toward both ends as shown by arrow I, and after the entire length of the central tear line 24a breaks, the side tear line 24c of the outer tear line 24b breaks as shown by arrow II, As shown in III, the tear lines 24d and 24e on the front and rear sides along the longitudinal direction of the outer tear line 24b are broken, and the door portion G is developed in a balanced manner.

  When the airbag 6 is deployed, the central tear line 24a breaks over its entire length, but the outer tear line 24b breaks over its entire length, and depending on temperature conditions, only the side tear lines 24c on both sides break, Some or all of the front and rear tear lines 24d and 24e along 34 may function as hinges that are easily bent without breaking.

  As described above, according to the present embodiment, the airbag 6 accommodated in the airbag device 1 for the passenger in the passenger seat of the automobile is covered, and is broken when the airbag 6 is inflated to form the protruding port 12. About the so-called seamless instrument panel cover body 11, the deformed line portion 39 that easily deforms to the inner portion 22 is formed crossing the middle position of the central tear line 24 a of the tear line 24 provided in the outer portion 21, so the planned door portion is deformed It becomes easy to do. Therefore, at the initial stage of inflation of the airbag 6, the vicinity of the break start position 27, which is a desired position of the planned door portion C, is greatly deformed, and the center tear line 24a is broken from the break start position 27 of the center portion. The airbag 6 can be cleaved along the tear line 24 without deviating from the tear line 24, the door portion G can be smoothly deployed in a balanced manner, and the airbag 6 can be deployed smoothly.

  And since the deformation line part 39 provided in the inner part 22 has been arrange | positioned symmetrically centering | focusing on the fracture | rupture start position 27 of the center tear line 24a, when the airbag 6 swells, the door expected part C Is deformed around the break start position 27, and can be easily broken from the break start position 27, which is a desired position of the central tear line 24a.

  Further, the deformation line portion 39 provided in the inner portion 22 extends in a direction orthogonal to the central tear line 24a, and is disposed between the hinge portions 34 along the deployment direction of the door portion G. The deformation line portion 39 can be formed without affecting the strong fixing structure by vibration welding of the hinge portion 34 to the outer portion 21 and the smooth deployment operation of the hinge portion 34 when the airbag 6 is inflated. .

  In this way, the cover body 11 can be broken from a desired breaking start position 27, and therefore, the so-called seamless instrument panel in which the inner portion 22 is overlapped and welded to the outer portion 21 ensures the deformability of the planned door portion C. The tear line 24 can be deployed from a desired position, the behavior of the cover body 11 can be easily controlled, and the deployment characteristics of the airbag 6 can be easily improved.

  Then, by forming the deformed line portion 39 provided with the concave groove, the cover body 11 can be easily and smoothly broken and deployed, so that a complicated structure is not required and the manufacturing cost can be reduced.

In this configuration, the outer portion 21 other than the airbag device 1 is formed by separating the inner portion 22 provided with the hinge portion 34 and the outer portion 21 provided with the tear line 24 as the planned door line portion. It is formed integrally with the member, so that the appearance can be easily improved. Further, by forming the support portion integrally with the hinge portion 34, the configuration is simplified and the manufacturing cost is reduced. Since the deformed line portion 39 is provided in the planned inner door portion 33, even if the planned outer door portion 26 and the planned inner door portion 33 are joined to form the planned door portion C, the planned door portion C can be deformed and broken. It becomes easy to break the central tear line 24a which is a line portion from a desired position.

  In addition, by adjusting the cross-sectional shape, the planar shape, and the like of the deformation line portion 39, the characteristic of breaking the cover body 11 can be adjusted. For example, as shown in FIG. 10, in the configuration in which four deformation line portions 39 are provided, the inner door of the inner portion 22 with respect to the center of the two deformation line portions 39 c on the side close to the fracture start position 27. By making the thickness dimension t1 of the resin constituting the planned portion 33 smaller than the thickness dimension t2 of the resin in the two deformation line portions 39d on both sides, that is, on the side away from the fracture start position 27, the center It is possible to easily break the portion at the break start position 27 side.

  Further, the number of the deformed line portions 39 is not limited to four, and an appropriate number of plural or single can be provided. When the odd number of deformation line portions 39 are set, the deformation line portion 39 located at the center can be formed so as to intersect the fracture start position 27 at the center portion.

  Further, although the inner fracture portion has been described as the completely cut portion 38, the inner fracture portion can be formed as a tear line that is connected by a resin in a state before deployment and easily breaks during deployment.

  In each of the above-described embodiments, the cover body 11 of the airbag device 1 for the passenger on the passenger seat of the instrument panel portion has been described. However, the cover of the airbag device installed in another place as the interior panel of the automobile It can also be applied to the body.

  Further, the cover body 11 has been described as constituting a part of the instrument panel portion. However, the cover body 11 is not limited to this configuration, and may be formed integrally with the entire length of the instrument panel portion.

  Furthermore, the cover body 11 is not limited to the structure in which the outer part 21 and the inner part 22 formed separately are joined, and the outer part 21 and the inner part 22 can be integrally formed.

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

It is a partial perspective view which shows one Embodiment of the cover body of the airbag apparatus of this invention. It is a disassembled perspective view of a part of cover body of an airbag apparatus same as the above. It is explanatory drawing of the IV-IV cross section equivalent position of FIG. 1 of an airbag apparatus same as the above. It is sectional drawing to which the part shown by the arrow V of FIG. 3 of the cover body of an airbag apparatus same as the above was expanded. It is explanatory drawing which shows operation | movement of the cover body of an airbag apparatus same as the above. It is a top view of the inner part of the cover body of an airbag apparatus same as the above. It is a bottom view of the inner part of the cover body of an airbag apparatus same as the above. It is the perspective view seen from the passenger | crew side of the inner part of the cover body of an airbag apparatus same as the above. It is IV-IV sectional drawing of FIG. 1 of the inner part of the cover body of an airbag apparatus same as the above. It is a partial sectional view showing one embodiment of a cover body of an airbag device of the present invention.

1 Airbag Device 6 Airbag
11 Cover body
12 Protrusion
21 Outer part
22 Inner part
24 Tear line as planned door line
24a Central tear line at the break line
24c side tear line
25 Outer shell
26 Outer door planned part
27 Break start position
31 Inner shell
33 Planned inner door
34 Hinge
39 Deformation line part A Upper part as bulging side C Door planned part D Outer part
G door

Claims (3)

A door that forms a door part that can be deployed by breaking at least partly due to the pressure when the airbag is inflated, and a door part that surrounds the door part that is arranged on the side of the airbag A cover body of an airbag device comprising a planned line portion , covering a bulging side of the stored airbag, and having a protruding port through which the airbag projects when the airbag is expanded,
An outer door planned portion disposed on the bulging side of the airbag, an outer shell portion surrounding the outer door planned portion, and an outer portion including the planned door line portion;
An inner door planned portion which is joined to the outer door planned portion and constitutes the door planned portion, an inner outer portion which is joined to the outer outer portion and constitutes the outer portion, and the inner door planned portion and the inner outer portion are connected. And an inner part provided with a deformation line part,
The door will line portion has a center tear line is the break line portion fracture start position is set with eclipsed set to a line shape extending on both sides positioned outer door scheduled portion, continuous with both ends of the center tear line And a side tear line extending forward and backward to partition the planned door portion and the outer portion,
The deformation line portion is located at the inner door planned portion, and is provided so as to be easily deformable from an adjacent portion of the door planned portion by recessing the inner portion, and at a middle position of a line segment of the central tear line. cover of an airbag device, characterized in that extending in the front and rear from the position of the central tear line intersect. Deformation line unit, the cover body of an airbag apparatus according to claim 1, characterized in that arranged symmetrically around the fracture starting point. A door scheduled portion and the outer Guo portion and a plurality of hinge portions deformable for connecting,
The cover body of the airbag apparatus according to claim 1, further comprising: a plurality of deformation line portions disposed between the hinge portions along a deployment direction of the door portion.

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