JP2012071754A - Air-bag system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress leakage of a gas to outside through a part between a support part and an inflator or a part between the support part and an air-bag housing.SOLUTION: The support part 55 elastically supporting the inflator 45 with respect to the air-bag housing (back holder 31) is provided with an inner support part 56, an outer support part 66, and an elastic coupling part 75. The inner support part 56 is formed by covering an inner hard member 57 of annular form which is disposed around the inflator 45, with an elastic material. The outer support part 66 is formed by covering an annular outer hard member 67, which is disposed around the inner hard member 57, with the elastic material. An elastic coupling part 75 is annularly formed only of the elastic material and couples the inner support part 56 and the outer support part 66. The inner support part 56 is fastened to a flange part 49 of the inflator 45 with a rivet 81. The outer support part 66 is fastened to the air-bag housing (back holder 31) with a bolt 42 and a nut 43.

Description

  The present invention relates to an airbag device installed in a steering wheel of a vehicle or the like. More specifically, the inflator is elastically supported via a support portion with respect to an airbag housing so as to function as a damper mass of a dynamic damper. The present invention relates to an airbag apparatus.

  If the vibration is transmitted to the steering wheel through the steering shaft while the vehicle is traveling at high speed or the engine is idling, there is a possibility that the driver's comfortable driving may be hindered. Therefore, a technique for suppressing (vibrating) the vibration of the steering wheel has been developed and proposed. For example, there is a technique that uses a dynamic damper including a weight and an elastic member that supports the weight on a metal core of a steering wheel. According to this technology, when vibration having the same frequency as the resonance frequency unique to the dynamic damper is transmitted from the steering wheel to the dynamic damper, the dynamic damper resonates and absorbs vibration energy of the steering wheel. This absorption suppresses (suppresses) the vibration of the steering wheel.

  On the other hand, an air bag device is incorporated in the steering wheel in order to protect the driver in the event of a vehicle collision. The airbag device includes an airbag and an inflator that supplies gas to the airbag, and protects the driver by inflating and deploying the airbag with the gas supplied from the inflator in a vehicle collision or the like. . Since this airbag device occupies most of the interior space of the steering wheel, it is difficult to interior the dynamic damper described above in a recent steering wheel. In view of this, a configuration has been proposed in which the inflator is elastically supported via a support portion with respect to the airbag housing so as to function as a damper mass of the dynamic damper.

  For example, in Patent Document 1, a cylindrical support portion (rubber diaphragm) having an axis of a steering wheel (inflator) as its own axis is used. In this support portion, an annular inner hard member (adapter element) is joined to one end portion in the direction along the axis by vulcanization. In the support portion, an annular outer hard member (connection plate) is joined to the other end portion in the direction along the axis by vulcanization. The inner hard member is fastened to the flange portion of the inflator by an inner fastening member such as a screw, and the outer hard member is fastened to the airbag housing by an outer fastening member such as a screw.

  In addition, in description about the said patent document 1, the name in the parenthesis following a member name is a member name currently used by the patent document 1. FIG.

JP 2001-171460 A

  However, in the above-mentioned Patent Document 1, hard members (the flange portion of the inflator and the inner hard member, the outer hard member and the airbag) are used at the fastening portion of the support portion with the inflator and the fastening portion of the support portion with the airbag housing. The housing) is fastened by a fastening member. For this reason, there is a considerable gap between the hard members to be fastened, and the gas ejected from the inflator may leak out of the airbag device from the gap.

  The present invention has been made in view of such circumstances, and its purpose is that gas leaks to the outside between the support portion and the inflator or between the support portion and the airbag housing. It is in providing the airbag apparatus which can suppress this.

  In order to achieve the above object, an invention according to claim 1 is directed to an air bag housing disposed in a steering wheel, an air bag attached to the air bag housing, and gas to the air bag. An airbag device comprising an inflator and a support part that elastically supports the inflator on the airbag housing, wherein the support part covers an annular inner hard member disposed around the inflator with an elastic material. An inner support part, an outer support part formed by covering an annular outer hard member disposed around the inner hard member with an elastic material, and the inner support part and the outer support. An annular elastic connecting part for connecting the parts, the inner support part is fastened to the inflator by an inner fastening member, and the outer support part is And gist that it is fastened to the airbag housing by side fastening member.

  In the airbag apparatus having the above-described configuration, the elastic coupling portion of the support portion functions as a dynamic damper spring, and the inflator functions as a dynamic damper damper mass. For this reason, when the vibration having the same frequency as the resonance frequency specific to the dynamic damper is transmitted from the steering wheel to the dynamic damper, the support portion (elastic connecting portion) and the inflator resonate to absorb the vibration energy of the steering wheel. This absorption attenuates (suppresses) the vibration of the steering wheel.

  By the way, when the airbag apparatus is operated by an impact such as a collision and gas is ejected from the inflator, most of the gas is supplied to the airbag and the airbag is inflated. At this time, there is a gap between the inner support portion and the inflator, which is a fastening portion between the support portion and the inflator, or between the outer support portion and the airbag housing, which is a fastening portion between the support portion and the airbag housing. If there is a gap, a part of gas from the inflator may leak out of the airbag device through these gaps.

  In this regard, in the first aspect of the invention, the inner support portion is formed by covering the annular inner hard member with an elastic material, and in the state where the inner support portion is fastened to the inflator, The elastic material around the member is elastically deformed and comes into close contact with the inflator. For this reason, a gap generated between the inner support portion and the inflator is extremely small. Therefore, the gas from the inflator does not easily leak out of the airbag device through this gap.

  In the first aspect of the invention, the outer support portion is formed by covering the annular outer hard member with an elastic material, and in the state where the outer support portion is fastened to the airbag housing, The elastic material around the hard member is elastically deformed and is in close contact with the airbag housing. For this reason, a gap generated between the outer support portion and the airbag housing is extremely small. Therefore, the gas from the inflator does not easily leak out of the airbag device through this gap.

  According to a second aspect of the present invention, in the first aspect of the present invention, the inner hard member and the outer hard member are formed with through-holes penetrating in the thickness direction, and both sides in the same thickness direction. The above-mentioned elastic material is connected through the through hole.

  According to said structure, in the inner side hard member and outer side hard member in which the through-hole was provided, the hard member is coat | covered with an elastic material from the both sides about the thickness direction. In addition, the elastic material located on both sides in the thickness direction of the hard member is in a state of being coupled by the elastic material filled in the through hole. Therefore, it is possible to integrate the hard member and the elastic material without using an adhesive.

  The invention according to claim 3 is the invention according to claim 1 or 2, wherein the inner support part and the outer support part are arranged at positions shifted in a direction along the axis of the inflator. And

The inner support portion and the outer support portion that are arranged in a manner that satisfies the above conditions are less likely to interfere with each other when vibration is transmitted from the steering wheel to the support portion.
The invention according to claim 4 is the invention according to any one of claims 1 to 3, wherein the inner hard member and the outer hard member are made of a plate material, and the outer shape of the outer hard member is itself The intermediate intermediate body is formed by processing a primary intermediate body, and among the primary intermediate bodies, the secondary intermediate body is formed by punching the primary intermediate body into the outer shape of the inner hard member. The outer hard member is formed from what remains, and further, the inner hard member is formed from what is left by punching the secondary intermediate into the inner shape of the inner hard member. The gist is that

  According to said structure, when forming an inner side hard member and an outer side hard member, the primary intermediate body which consists of board | plate material and has the external shape of the same external hard member as its external shape is used as a process target. A secondary intermediate is formed by punching the primary intermediate into the outer shape of the inner hard member, and an outer hard member is formed by applying appropriate processing to the remaining intermediate. Further, the inner rigid member is formed by subjecting the secondary intermediate body to the inner shape of the inner rigid member left after being appropriately processed.

  Thus, an inner hard member is formed from the secondary intermediate formed by punching the primary intermediate. For this reason, less plate material is required for forming the inner hard member, and the yield is improved.

  The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the airbag housing has a peripheral portion of the opening portion of the airbag in a direction along the axis of the inflator. A back holder and a retainer sandwiched from both sides are provided, and the back holder and the retainer are provided with a phase matching portion for matching the phase of the retainer with respect to the back holder around the axis, the phase matching portion, A locking hole provided in one of the back holder and the retainer, and a locking projection provided in the other and engaged with the locking hole, the locking hole and the locking projection are The gist is provided between the outer support portion and the inflator.

  According to said structure, the peripheral part of the opening part is fixed to an airbag housing by being pinched | interposed by the back holder and a retainer from the both sides of the direction in alignment with the axis of an inflator. Prior to this fixing, the phase of the retainer relative to the back holder around the axis is matched by the phase matching section. This phase alignment is performed by engaging a locking projection provided on the other side with respect to a locking hole provided on one of the back holder and the retainer. When a gap is generated between the locking projections in the locking hole as described above, this gap can be a gas flow path.

  However, in the invention described in claim 5, the locking hole and the locking projection are provided between the outer support portion and the inflator, that is, inside the support portion. Therefore, even if the gas flows between the locking hole and the locking projection as described above, the gas flow is performed in the space inside the support portion, and the outside of the airbag device. It is hard to leak.

  The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein the support portion is provided with an exhaust hole penetrating the elastic connecting portion in the thickness direction. The gist.

  When it is necessary to adjust the gas pressure inside the airbag device, the support portion may be provided with an exhaust hole penetrating the elastic connecting portion in the thickness direction. . In this case, a part of the gas inside the airbag device is discharged to the outside of the airbag device through the exhaust hole, so that the pressure of the gas inside the airbag device is adjusted.

  For example, in the airbag apparatus in which the inflator is not elastically supported on the airbag housing by the support portion, although the phase matching portion as in the invention described in claim 5 is provided, the gas from the inflator is The air leaks out of the airbag device from the gap between the locking hole and the locking projection. If there is a demand for the pressure of the gas inside the airbag device to be comparable to that of this type of airbag device, it can be easily dealt with by providing the exhaust holes as described above.

  According to the airbag device of the present invention, gas can be prevented from leaking to the outside through the support portion and the inflator or between the support portion and the airbag housing.

The rear view which shows the state which looked at the steering wheel with an airbag apparatus in one Embodiment which actualized this invention from the vehicle rear. The fragmentary sectional view which shows the internal structure of the right half of the steering wheel in FIG. The fragmentary sectional view which expands and shows a part of airbag apparatus in FIG. (A) is a front view which shows the state which looked at the support part from the vehicle front, (B) is sectional drawing which shows the cross-section of the support part in the state which abbreviate | omitted one part. (A) is a front view of the inner side hard member in an inner side support part, (B) is sectional drawing of the support part which shows the cross-section of the direction in alignment with the XX line of FIG. 4 (B). (A) is a front view of the outer side hard member in an outer side support part, (B) is sectional drawing of the support part which shows the cross-section of the direction in alignment with the YY line of FIG. 4 (B). (A)-(E) are explanatory drawings which show the procedure which forms an outer side hard member and an inner side hard member from a board | plate material. The fragmentary sectional view which shows another example of an airbag apparatus.

Hereinafter, an embodiment in which the present invention is embodied in a steering wheel with an airbag device will be described with reference to FIGS.
As shown in at least one of FIGS. 1 and 2, a steering shaft (steering shaft) 11 that rotates about the rotation axis L1 is tilted so as to be higher toward the driver's seat in front of the driver's seat of the vehicle. It is arranged in a state. A steering wheel 12 is attached to the rear end portion of the steering shaft 11 so as to be integrally rotatable. The steering wheel 12 includes a rim portion (sometimes referred to as a handle portion or a ring portion) 13, a pad portion 14, and a spoke portion 15.

  The rim portion 13 has a substantially annular shape centering on the steering shaft 11 (see FIG. 1). The pad portion 14 is disposed in a space surrounded by the rim portion 13. The front portion of the pad portion 14 is constituted by a lower cover 16 (see FIG. 2). A plurality of spoke portions 15 are provided between the rim portion 13 and the pad portion 14.

  In the present embodiment, when describing each part of the steering wheel 12, the rotation axis L1 of the steering shaft 11 is used as a reference. The direction along the rotational axis L1 is referred to as the “front-rear direction” of the steering wheel 12, and the direction in which the steering wheel 12 stands up is referred to as the “vertical direction” among the directions along the plane orthogonal to the rotational axis L1. Therefore, the front-rear direction and the vertical direction of the steering wheel 12 are slightly inclined with respect to the front-rear direction (horizontal direction) and the vertical direction (vertical direction) of the vehicle.

  Further, in order to specify the position of the steering wheel 12 to be rotated, in this embodiment, “up”, “down” based on the state of the steering wheel 12 when the vehicle is traveling straight, that is, the neutral state. , “Left” and “Right” shall be defined. Therefore, the left-right direction of the steering wheel 12 is the same as the vehicle width direction (vehicle width direction).

  A cored bar 20 made of iron, aluminum, magnesium, or an alloy thereof is disposed inside each of the above-described constituent members (the rim portion 13, the pad portion 14, and the spoke portion 15) of the steering wheel 12. . The core metal 20 forms a skeleton part of the steering wheel 12, and includes a substantially annular ring core metal 21, a boss core metal 22 positioned substantially at the center of the ring core metal 21, and a ring core metal. 21 and a spoke cored bar 23 that connects the bossed cored bar 22.

  The core metal 20 having the above-described configuration is attached to the rear end portion of the steering shaft 11 at the boss core metal 22 so as to be integrally rotatable. In the cored bar 20, the ring part cored bar 21 and the portion of each spoke part cored bar 23 near the ring part cored bar 21 are covered with a coating part 24 (see FIG. 2) made of a soft resin or the like, and further on the outside. The skin 25 (refer FIG. 1) which consists of leather etc. is covered. In FIG. 2, illustration of the skin 25 is omitted.

  In the core metal 20, the entire boss core metal 22 and the portions of the spoke cores 23 near the boss core 22 are covered from the front side by the lower cover 16. The lower cover 16 is formed in a plate shape from a hard resin or the like, and is fastened and fixed to the cored bar 20 by a fastening member (not shown) such as a screw.

  As shown in at least one of FIGS. 2 and 3, an airbag device 30 is disposed inside the pad portion 14. The airbag device 30 includes a back holder 31, a cup retainer 35, an airbag 40, an inflator (gas generator) 45, and a support portion 55. Next, these structural members of the airbag device 30 will be described.

<Back holder 31>
The back holder 31 is mainly for holding the airbag 40 and has a substantially bottomed box shape that opens rearward. The back holder 31 has a circular insertion hole 32 on its bottom wall that is slightly larger in diameter than the inflator 45. The back holder 31 is formed with an annular protrusion 34 that protrudes rearward from the insertion hole 32. The annular protrusion 34 is located between the inflator 45 and the opening 41 of the airbag 40 so that the gas G ejected from the inflator 45 does not directly hit the opening 41.

  Further, in the back holder 31, an escape hole 29 is formed at a location behind a rivet 81 described later. The escape hole 29 is for avoiding the tip 81 </ b> T of the rivet 81 from contacting the back holder 31 when the rivet 81 vibrates back and forth with the elastic deformation of the support portion 55.

  The back holder 31 is supported by the cored bar 20 via a plurality of horn switch mechanisms 33 (see FIG. 2) for operating a horn device (not shown) provided in the vehicle. By this support, the airbag device 30 is in a floating state with respect to the cored bar 20. Therefore, the airbag device 30 can be moved (displaced) in the front-rear direction by deforming each horn switch mechanism 33.

<Cup retainer 35>
The cup retainer 35 is mainly used when the peripheral portion of the opening 41 in the airbag 40 is sandwiched between the back holder 31 and fastened, and is disposed on the rear side of the back holder 31. The cup retainer 35 has a substantially box shape that opens forward. A cover portion 36 is formed at the center portion of the cup retainer 35 so as to bulge in a cup shape toward the rear and cover the inflator 45 from the rear side. The cover portion 36 is formed with a gas discharge port 37 through which the gas G ejected from the inflator 45 is discharged from the cup retainer 35 to the airbag 40.

The cup retainer 35 and the back holder 31 constitute an airbag housing.
<Airbag 40>
The airbag 40 is inflated by the gas G discharged from the gas discharge port 37 of the cup retainer 35, and is formed into a bag shape with a cloth such as a woven cloth having high strength and flexibility. The airbag 40 has an opening 41 at its front end. The opening 41 is located in the radially outer vicinity of the annular protrusion 34 of the back holder 31. The peripheral portion of the opening 41 in the airbag 40 is sandwiched by the cup retainer 35 and the back holder 31 from both sides (front and rear sides) in the direction along the axis L2 of the inflator 45. In this embodiment, the axis L2 of the inflator 45 is located on the same straight line as the rotation axis L1 of the steering shaft 11.

  The airbag 40 is fastened to the back holder 31 together with the cup retainer 35 by a bolt 42 and a nut 43 in the peripheral portion of the opening 41. As the bolt 42, for example, a caulking stud that is caulked and fixed to the cup retainer 35 may be used. In this way, the airbag 40 is attached to the airbag housing (the back holder 31 and the cup retainer 35).

Many parts except the opening part 41 of the airbag 40 are arrange | positioned in the back side rather than the cup retainer 35 in the folded state (refer FIG. 2).
<Inflator 45>
The inflator 45 is for supplying the gas G to the airbag 40, and its outer shell is constituted by a substantially cylindrical case 46. A gas generating agent (not shown) that generates gas G for inflating the airbag 40 is accommodated in the case 46.

  A plurality of gas ejection holes 48 are provided in the circumferential direction 47 of the case 46 at substantially equal angles in the circumferential direction, and the gas G generated by the gas generating agent passes through each gas ejection hole 48 in the radial direction of the inflator 45. Spouted outward.

  An annular flange portion 49 is formed over the entire circumference of the peripheral wall portion 47 at a location on the peripheral wall portion 47 and in front of the gas ejection hole 48. A part of the flange portion 49 is a mounting piece 51 that extends radially outward from a plurality of locations around the axis L2. Each attachment piece 51 has a rivet insertion hole 52 (see FIG. 3).

  In addition, a connector 53 is assembled to the front central portion of the case 46, and a harness (not shown) serving as an operation signal application wiring to the inflator 45 is connected to the connector 53.

  As the inflator 45, a type in which a partition of a high-pressure gas cylinder filled with a high-pressure gas is broken with an explosive or the like to eject gas may be used instead of the type using the gas generating agent.

<Supporting part 55>
As shown in at least one of FIGS. 3 and 4 (A) and (B), the support portion 55 is for elastically supporting the inflator 45 on the airbag housing, and between the inflator 45 and the back holder 31. Intervened.

The support part 55 includes an inner support part 56, an outer support part 66, and an elastic connection part 75.
The inner support portion 56 includes an inner hard member 57 disposed around the peripheral wall portion 47 of the inflator 45. As shown in at least one of FIGS. 4A and 4B and FIGS. 5A and 5B, the inner rigid member 57 is located on a plane orthogonal to the axis L <b> 2 of the inflator 45. The inner hard member 57 is formed of a metal plate having a predetermined thickness, for example, about 1 mm. The inner rigid member 57 is mainly used as a strength member for securing the coupling strength between the inner support portion 56 and the inflator 45 (flange portion 49).

  The inner rigid member 57 has a shape corresponding to the flange portion 49 of the inflator 45. Specifically, the inner hard member 57 includes an annular main body portion 58 corresponding to the portion excluding the attachment piece 51 in the flange portion 49, and a plurality of locations around the axis L <b> 2 of the main body portion 58 corresponding to the attachment piece 51. And an attachment piece 59 extending radially outward. Through holes 61 that penetrate in the thickness direction (front-rear direction) of the main body portion 58 are formed at a plurality of locations that are separated from each other in the circumferential direction of the main body portion 58. Each attachment piece 59 has a rivet insertion hole 62 corresponding to the rivet insertion hole 52 of the attachment piece 51.

  The inner shape of the inner rigid member 57 is a circle having a slightly larger diameter than the peripheral wall portion 47 of the inflator 45. As for the outer shape of the inner support portion 56, the main body portion 58 has an arc shape with a small curvature, and the attachment piece 59 has an arc shape with a larger curvature than the main body portion 58.

  An inner covering portion 63 made of an elastic material such as an elastomer is formed around the inner hard member 57. The elastic material is not filled in the rivet insertion hole 62 but is filled in the through hole 61. The inner support member 56 is configured by the inner hard member 57 and the inner covering portion 63. In the inner covering portion 63, both side portions in the thickness direction of the inner hard member 57 are connected to each other through the through hole 61. By such connection through the through hole 61, the inner hard member 57 and the inner covering portion 63 are integrated. No adhesive is used for this integration.

  On the other hand, the outer support portion 66 includes an outer hard member 67 disposed around the inner hard member 57. As shown in at least one of FIGS. 4A and 4B and FIGS. 6A and 6B, the outer rigid member 67 is located on a plane orthogonal to the axis L <b> 2 of the inflator 45. This surface is located at a position slightly shifted backward from the inner hard member 57, which is the direction along the coaxial line L2. Therefore, the inner hard member 57 and the outer hard member 67 are arranged in parallel to each other at a location shifted in the direction along the axis L2.

  The outer hard member 67 is formed of a metal plate having the same thickness as the inner hard member 57. The outer rigid member 67 is mainly used as a strength member for ensuring the coupling strength between the outer support portion 66 and the back holder 31.

  The outer hard member 67 has a substantially rectangular outer shape in the present embodiment, but is not limited thereto. The outer hard member 67 has an inner shape corresponding to the outer shape of the inner hard member 57, which is the same inner shape in this embodiment. The inner shape of the outer rigid member 67 is a circular arc having a small curvature at a portion corresponding to the portion of the flange portion 49 of the inflator 45 excluding the attachment piece 51, and a circle having a large curvature at the portion corresponding to each attachment piece 51. It has an arc shape. Here, in order to distinguish the inner shape of the outer support portion 66, the former is referred to as a large arc portion 68, and the latter is referred to as a small arc portion 69 having a smaller diameter than the large arc portion 68.

  Through holes 71 that penetrate in the thickness direction (front-rear direction) of the outer hard member 67 are formed at a plurality of locations separated from each other in the circumferential direction of the outer hard member 67. Further, in the outer hard member 67, bolt insertion holes 72 are formed at a plurality of locations slightly apart from the small arc portions 69 in the circumferential direction. Accordingly, each bolt insertion hole 72 is located at a position slightly deviated in the circumferential direction around the axis L2 with respect to each rivet insertion hole 52, 62.

  An outer covering portion 73 made of an elastic material such as an elastomer is formed around the outer hard member 67 in the same manner as the inner covering portion 63. The elastic material is not filled in the bolt insertion holes 72 but is filled in the through holes 71. The outer hard member 67 and the outer covering portion 73 constitute an outer support portion 66. In the outer covering portion 73, both side portions in the thickness direction of the outer hard member 67 are connected to each other through the through hole 71. Due to the connection through the through hole 71, the outer hard member 67 and the outer covering portion 73 are integrated. No adhesive is used for this integration.

  Here, as described above, since the inner hard member 57 and the outer hard member 67 are arranged in parallel with each other at a position shifted in the direction along the axis L2, the inner support portion 56 and the outer support portion 66 are disposed. Are also arranged in parallel to each other at positions shifted in the direction along the axis L2.

  The elastic connecting portion 75 is formed in an annular shape only by the same elastic material as the inner covering portion 63 and the outer covering portion 73, and includes the inner support containing hard members (the inner hard member 57 and the outer hard member 67). It is easier to elastically deform than the part 56 and the outer support part 66. The front end portion of the elastic connecting portion 75 is connected to the outer edge portion of the inner support portion 56, and the rear end portion of the elastic connecting portion 75 is connected to the inner edge portion of the outer support portion 66. The elastic connecting portion 75 has a shape corresponding to the outer shape of the inner hard member 57 and the inner shape of the outer hard member 67. That is, the elastic coupling portion 75 has a large arc portion 78 having a small arc shape corresponding to the portion of the flange portion 49 excluding the mounting piece 51 and an arc shape having a large curvature corresponding to each mounting piece 51. And a small arc portion 79 formed.

  The elastic connecting portion 75 constitutes a dynamic damper together with the inflator 45 described above. In the present embodiment, the elastic connecting portion 75 functions as a dynamic damper spring, and the inflator 45 functions as a damper mass.

  Further, in the present embodiment, by tuning the size, thickness, height, and the like of the elastic connecting portion 75, the resonance frequency in the vertical direction and the horizontal direction of the dynamic damper is increased in the vertical direction of the steering wheel 12 with the airbag device. For the vibration in the left and right directions, the target vibration suppression frequency (frequency to be controlled) is set.

  The support portion 55 having the above-described configuration is, for example, an inner hard member 57 and an outer hard member 67 that are disposed as insert members in a mold, and an elastic material is placed around the inner hard member 57 and the outer hard member 67. The inner hard member 57 and the outer hard member 67 are integrated with the elastic material by so-called insert molding.

  In the support portion 55, as shown in FIG. 3, the inner support portion 56 of the support portion 55 is overlapped with the flange portion 49 of the inflator 45 from the front side. Then, the rivet 81 is inserted into the rivet insertion holes 52 and 62 of the attachment pieces 51 and 59, and the tip end portion 81T of the rivet 81 is crushed, whereby the inner support portion 56 is fastened (fixed by caulking) to the flange portion 49. ) In the present embodiment, the rivet 81 constitutes an inner fastening member that fastens the inner support portion 56 to the inflator 45.

  As described above, in a state where the inner support portion 56 is fastened to the inflator 45, the inner covering portion 63 in the inner support portion 56 is elastically deformed and is in close contact with the flange portion 49, and the inner support portion 56, the flange portion 49, The gap generated between the two is extremely small.

  Further, the outer support portion 66 is overlapped with the back holder 31 from the front side, and is fastened to the back holder 31 by the bolts 42 and nuts 43 described above together with the airbag 40 and the cup retainer 35. That is, the shaft portion 42A of the bolt 42 inserted through the cup retainer 35, the airbag 40, and the back holder 31 is inserted into the bolt insertion hole 72, and the nut 43 is screwed into the shaft portion 42A from the front side. A support portion 66 is fastened to the back holder 31. In the present embodiment, these bolts 42 and nuts 43 constitute an outer fastening member that fastens the outer support portion 66 to the back holder 31.

  As described above, in a state in which the outer support portion 66 is fastened to the back holder 31, the outer covering portion 73 in the outer support portion 66 is elastically deformed to be in close contact with the back holder 31, and the outer support portion 66 and the back holder 31. The gap formed between the two is extremely small.

  The inner hard member 57 and the outer hard member 67 described above are made of a plate material and have the outer shape of the outer hard member 67 as its outer shape, as compared to the primary intermediate body 85 shown in FIG. It is formed by processing. The primary intermediate body 85 is punched into the outer shape of the inner hard member 57, whereby a secondary intermediate body 86 shown in FIG. 7C is formed. A bolt insertion hole 72 and a through-hole 71 are formed in the portion (remaining portion 87) shown in FIG. 7B, which is left by punching out the secondary intermediate 86 from the primary intermediate 85, so that the outer hard A member 67 is formed. Further, a rivet insertion hole 62 is formed in the secondary intermediate body 86 shown in FIG. When the secondary intermediate body 86 is punched into the inner shape of the inner hard member 57, a disk 89 shown in FIG. 7E is formed. The inner hard member 57 is formed by punching the through hole 61 in the portion (remaining portion 88) shown in FIG. The rivet insertion hole 62 may be formed at the same timing as the through hole 61.

  As described above, the steering wheel 12 with the airbag device of the present embodiment is configured. In the steering wheel 12, when the driver presses the pad portion 14 shown in FIG. 2, the back holder 31 is displaced forward together with the airbag device 30. By this displacement, the horn switch mechanism 33 is closed, and the horn device is activated (sounds).

  In the airbag device 30, the gas G is not ejected from the gas ejection holes 48 of the inflator 45 and the airbag 40 is not normally ejected from the front due to a frontal collision (front collision) or the like. It is kept in a folded state.

  Further, in the normal time, when the vehicle is traveling at high speed or the engine is idling, vibrations in the vertical direction and the horizontal direction may be transmitted to the steering wheel 12 through the steering shaft 11. In the airbag device 30, this vibration is transmitted to the inflator 45 through the back holder 31 and the support portion 55 as shown in FIG. 3. At this time, in the support portion 55, both the outer hard member 67 and the inner hard member 57 function as strength members.

  In response to the vibration, in the airbag device 30, the elastic coupling portion 75 of the support portion 55 functions as a dynamic damper spring, and the inflator 45 functions as a dynamic damper damper mass.

  For example, when the steering wheel 12 vibrates in the vertical direction at a predetermined frequency, the elastic coupling portion 75 of the support portion 55 vibrates in the vertical direction with the inflator 45 at a resonance frequency that is the same as or close to that frequency (resonance). The vibration energy in the vertical direction of the steering wheel 12 is absorbed. Due to this absorption, vibration in the vertical direction of the steering wheel 12 is suppressed (damped).

  Further, when the steering wheel 12 vibrates in the left-right direction at a predetermined frequency, the elastic connecting portion 75 of the support portion 55 vibrates in the left-right direction with the inflator 45 while elastically deforming at a resonance frequency equal to or close to the frequency. Absorbs vibration energy in the left-right direction of the wheel 12. By this absorption, the vibration in the left-right direction of the steering wheel 12 is attenuated (damped).

In this way, in the present embodiment, the steering wheel 12 is damped (damped) in both the vertical and horizontal directions.
Here, when the inflator 45 elastically supported by the airbag housing (back holder 31) via the support portion 55 vibrates in the front-rear direction, the crushed tip 81T approaches the back holder 31. There is a risk of contact. In this regard, in the present embodiment, the escape hole 29 is formed at a location corresponding to the rivet insertion hole 62 in the back holder 31. Therefore, when the tip 81T of the rivet 81 enters the escape hole 29, the contact is avoided, and the hitting sound associated with the contact is less likely to occur.

  Further, the inner support portion 56 and the outer support portion 66 may interfere with each other when the vibration is transmitted from the steering wheel 12 to the support portion 55 and displaced. In this respect, in the present embodiment, the inner support portion 56 and the outer support portion 66 are arranged at positions shifted in the direction along the axis L2 of the inflator 45. Therefore, the inner support portion 56 and the outer support portion 66 are disposed. Are less likely to interfere with each other when the vibration is transmitted from the steering wheel 12 to the support portion 55 and displaced.

  By the way, when an impact is applied to the vehicle from the front due to a front collision or the like, the driver tends to lean forward due to inertia. On the other hand, in the airbag device 30, the gas G is supplied to the airbag 40 from each gas ejection hole 48 of the inflator 45 in response to the impact. By this gas G, the airbag 40 is inflated toward the rear side (driver side). Due to this inflating airbag 40, a pressing force is applied to the pad portion 14, and the pad portion 14 is broken at a preset location. The airbag 40 is inflated and deployed rearward through the opening generated by the breakage. The inflated and deployed airbag 40 is interposed between the steering wheel 12 and the driver who wants to tilt forward due to the impact of the front collision, and the forward tilt of the driver is restrained and protected from the impact.

  The gas G ejected from the gas ejection hole 48 of the inflator 45 flows outward in the radial direction of the inflator 45 as indicated by an arrow in FIG. Since the opening 41 of the airbag 40 is located in the vicinity of the gas ejection hole 48, the gas G ejected from the gas ejection hole 48 may directly touch the opening 41. In this regard, in the present embodiment, the annular protrusion 34 that protrudes rearward from the insertion hole 32 of the back holder 31 is located between the gas ejection hole 48 and the opening 41 of the airbag 40. The annular protrusion 34 prevents the gas G ejected from the gas ejection hole 48 from directly hitting the opening 41. Therefore, it is suppressed that the gas G touches the opening part 41 of the airbag 40 directly, and receives the bad influence (melting damage etc.) by heat.

  As described above, when the gas G is ejected, there is a gap in the fastening portion between the support portion 55 and the back holder 31, or there is a gap in the fastening portion between the support portion 55 and the inflator 45 (flange portion 49). In some cases, part of the gas G from the inflator 45 may leak out of the airbag device 30 through these gaps.

  In this regard, in the present embodiment, in a state where the inner support portion 56 is fastened to the flange portion 49 of the inflator 45, the inner covering portion 63 is elastically deformed and is in close contact with the flange portion 49. Therefore, the gap generated between the inner support portion 56 and the flange portion 49 is extremely small. Accordingly, the gas G from the inflator 45 is less likely to leak out of the airbag device 30 through this gap.

  Similarly, in the present embodiment, in a state where the outer support portion 66 is fastened to the back holder 31, the outer covering portion 73 is elastically deformed and comes into close contact with the back holder 31. Therefore, a gap generated between the outer support portion 66 and the back holder 31 is extremely small. Accordingly, the gas G from the inflator 45 is less likely to leak out of the airbag device 30 through this gap.

According to the embodiment described in detail above, the following effects can be obtained.
(1) As the support portion 55 that elastically supports the inflator 45 on the airbag housing (back holder 31), a device including an inner support portion 56, an outer support portion 66, and an elastic connection portion 75 is used. As the inner support portion 56, an annular inner hard member 57 disposed around the peripheral wall portion 47 of the inflator 45 is covered with an elastic material. As the outer support portion 66, an annular outer hard member 67 disposed around the inner hard member 57 is covered with an elastic material. As the elastic connecting portion 75, an elastic connecting portion that is formed in an annular shape by only an elastic material and connects the inner support portion 56 and the outer support portion 66 is used. The inner support portion 56 is fastened to the flange portion 49 of the inflator 45 by the inner fastening member (rivet 81), and the outer support portion 66 is fastened to the airbag housing (back holder 31) by the outer fastening member (bolt 42 and nut 43). It is made to fasten (FIG. 3).

  Therefore, the gap between the inner support portion 56 and the inflator 45 (flange portion 49) is compared with the case where the inner hard member is fastened in contact with the flange portion of the inflator (Patent Document 1 corresponds to this). The gas G can be prevented from leaking out of the airbag device 30 through the gap. Moreover, compared with the case where it fastens in the state which made the outer side hard member contact the airbag housing (back holder) (patent document 1 corresponds to this), it is the outer side support part 66 and the airbag housing (back holder 31). It is possible to reduce the gap between them and prevent the gas G from leaking out of the airbag device 30 through this gap.

  (2) The through hole 61 is formed in the inner hard member 57 so as to penetrate in the thickness direction. Then, the inner hard member 57 is covered with the inner covering portion 63 made of the elastic material in a state where a part of the elastic material is filled in the through hole 61, whereby the inner hard member 57 has a thickness. Portions located on both sides of the direction are connected through the through hole 61 (FIG. 4B).

For this reason, the inner hard member 57 and the inner covering portion 63 can be integrated without using an adhesive.
Further, a through hole 71 that penetrates in the thickness direction is formed in the outer hard member 67. Then, the outer hard member 67 is covered with the outer covering portion 73 made of the elastic material in a state where a part of the elastic material is filled in the through hole 71, so that the thickness of the outer hard member 67 is increased in the outer covering portion 73. Portions located on both sides of the direction are connected through the through hole 71 (FIG. 4A).

For this reason, the outer hard member 67 and the outer covering portion 73 can be integrated without using an adhesive.
(3) The inner side support part 56 and the outer side support part 66 are arrange | positioned in the location shifted | deviated to the direction in alignment with the axis line L2 of the inflator 45 (FIG. 3).

  For this reason, vibration is transmitted from the steering wheel 12 to the support portion 55, and the elastic coupling portion 75 is elastically deformed, so that it is possible to suppress interference between the inner support portion 56 and the outer support portion 66 when they are displaced.

  (4) A primary intermediate body 85 made of a plate material and having the outer shape of the outer hard member 67 as its outer shape is a processing target. The secondary intermediate body 86 is formed by punching the primary intermediate body 85 into the outer shape of the inner hard member 57, and the outer hard member 67 is formed from the remaining portion 87. Further, the secondary intermediate body 86 is punched into the inner shape of the inner hard member 57, and the inner hard member 57 is formed from the remaining portion 88 (FIGS. 7A to 7E).

  Thus, since the inner hard member 57 is formed from the secondary intermediate 86 formed by punching out of the primary intermediate 85, less plate material is required for forming the inner hard member 57, and the yield is reduced. improves.

(5) The elastic connecting portion 75 of the support portion 55 is formed in an annular shape along the outer shape of the inner hard member 57 (the inner shape of the outer hard member 67) (FIG. 6A).
Therefore, the space surrounded by the elastic coupling part 75 can be reduced, and the support part 55 can be made compact.

(6) Each bolt insertion hole 72 is formed at a location slightly displaced in the circumferential direction about the axis L2 of the inflator 45 with respect to each rivet insertion hole 62 (FIG. 4A).
Therefore, each bolt insertion hole 72 can be formed closer to the axis L2 than when formed at the same position (same phase) in the circumferential direction around the axis L2. As a result, the outer rigid member 67 and the outer support portion 66 can be reduced in size, and in this respect also, the support portion 55 can be made compact.

Note that the present invention can be embodied in another embodiment described below.
-At least one of the inner hard member 57 and the outer hard member 67 may be formed of a hard material different from metal.

  In the airbag device 30 that fixes the peripheral portion of the opening portion 41 of the airbag 40 by the back holder 31 and the cup retainer 35 from both sides in the direction along the axis L2 of the inflator 45, the phase around the axis L2 There is a possibility that the cup retainer 35 may be assembled to the back holder 31 in an incorrect state. Therefore, in the airbag device, a phase aligning unit for aligning the phase of the cup retainer with respect to the back holder around the axis may be provided in the back holder and the cup retainer.

  Also in this embodiment, a phase matching unit similar to the above may be provided. Specifically, the phase matching portion includes a locking hole provided in one of the back holder and the retainer, and a locking protrusion provided in the other and engaged with the locking hole.

  FIG. 8 shows an example in which the locking hole 92 of the phase matching portion 91 is opened in the back holder 31 and the locking projection 93 is formed in the cup retainer 35. The locking projection 93 is formed by cutting and raising a part of the cup retainer 35 downward.

  In such a configuration, the phase of the cup retainer 35 relative to the back holder 31 around the axis L <b> 2 is adjusted by the phase matching unit 91 prior to the attachment of the airbag 40 to the airbag housing (back holder 31 and cup retainer 35). This phase alignment is performed by engaging the locking projection 93 of the cup retainer 35 with the locking hole 92 of the back holder 31.

However, in such a state where the locking projection 93 is engaged with the locking hole 92, a gap is often generated between them, and this gap can be a flow path for the gas G.
Therefore, as shown in FIG. 8, it is desirable that the locking hole 92 and the locking projection 93 are provided between the outer support portion 66 and the inflator 45. In this way, even if the gas G flows between the locking hole 92 and the locking projection 93 as described above, the flow of the gas G is in a space radially inward of the support portion 55. As a result, the air bag device 30 will not leak out.

  If it is necessary to adjust the pressure of the gas G inside the airbag device 30, as shown in FIG. 8, the support portion 55 may be provided with an exhaust hole 94 that penetrates the elastic connecting portion 75 in the thickness direction. Good. If it does in this way, a part of gas G inside the airbag apparatus 30 will be discharged | emitted outside the airbag apparatus 30 through the exhaust hole 94, and the pressure of the gas G inside the airbag apparatus 30 will fall. .

  For example, in an airbag apparatus of a type in which a phase matching section similar to the phase matching section 91 is provided but the inflator is not elastically supported by the airbag housing by the support section, the gas from the inflator It leaks out of the air bag device from the gap between the hole and the locking projection. If there is a demand for the pressure of the gas G inside the airbag device 30 to be the same as that of the above-described type of airbag device, it can be easily dealt with by providing the exhaust hole 94 as described above. Is possible.

The peripheral wall 47 of the inflator 45 may have a cylindrical shape other than a cylindrical shape.
-As an inner side fastening member, a volt | bolt and a nut may be used similarly to the said outer side fastening member.

Moreover, a rivet may be used as an outer side fastening member similarly to the said inner side fastening member.
Furthermore, members other than the bolt, nut, and rivet may be used as the inner fastening member and the outer fastening member.

The shape of the elastic connecting portion 75 may be changed to a shape that does not correspond to the outer shape of the inner hard member 57 (the inner shape of the outer hard member 67), for example, an annular shape or a square ring shape.
-You may form the escape hole 29 in FIG. 3 in the magnitude | size which the rivet 81 can enter from the front-end | tip part 81T. In this way, when the rivet 81 is displaced in the front-rear direction in accordance with the elastic deformation of the support portion 55 (elastic connecting portion 75), the tip portion 81T of the rivet 81 enters the escape hole 29 and is softened by the airbag 40. It is possible to suppress the occurrence of a hitting sound.

  DESCRIPTION OF SYMBOLS 12 ... Steering wheel, 30 ... Airbag apparatus, 31 ... Back holder (comprising a part of airbag housing), 35 ... Cup retainer (Retainer constituting a part of airbag housing), 40 ... Airbag, 41 ... Opening part, 42 ... bolt (constituting part of the outer fastening member), 43 ... nut (constituting part of the outer fastening member), 45 ... inflator, 55 ... supporting part, 56 ... inner supporting part, 57 ... inner hard Members 61, 71 through holes, 66 outer support portions, 67 hard outer members, 75 elastic connecting portions, 81 rivets (constituting inner fastening members), 85 primary intermediates, 86 secondary intermediates , 87, 88 ... remaining portion, 91 ... phase matching portion, 92 ... locking hole, 93 ... locking projection, 94 ... exhaust hole, G ... gas, L2 ... axis of inflator.

Claims (6)

An airbag housing disposed in the steering wheel; an airbag attached to the airbag housing; an inflator for supplying gas to the airbag; and a support portion for elastically supporting the inflator on the airbag housing. An airbag device comprising:
The support part is
An inner support portion formed by coating an annular inner hard member disposed around the inflator with an elastic material;
An outer support portion formed by coating an annular outer hard member disposed around the inner hard member with an elastic material;
And an annular elastic connecting portion that is formed only by an elastic material and connects the inner support portion and the outer support portion. The inner support portion is fastened to the inflator by an inner fastening member, and the outer support portion is fastened to the outside. An airbag device, wherein the airbag device is fastened to the airbag housing by a member. The through hole which penetrates in the thickness direction is formed in the inner side hard member and the outer side hard member, and the elastic material of the both sides about the thickness direction is connected through the through hole. Airbag device. The airbag device according to claim 1 or 2, wherein the inner support portion and the outer support portion are disposed at locations shifted in a direction along the axis of the inflator. The inner hard member and the outer hard member are made of a plate material, and are formed by processing a primary intermediate having the outer shape of the outer hard member as its outer shape,
Among the primary intermediates, the primary intermediate is punched into the outer shape of the inner hard member is a secondary intermediate, and the outer hard member is formed from the remaining one,
Furthermore, the said inner side hard member is formed from what was left after stamping out the said secondary intermediate body in the internal shape of the said inner side hard member among the said secondary intermediate bodies. The airbag apparatus as described. The airbag housing includes a back holder and a retainer that sandwich a peripheral portion of the opening of the airbag from both sides in a direction along the axis of the inflator,
The back holder and the retainer are provided with a phase matching portion for matching the phase of the retainer with respect to the back holder around the axis,
The phase adjusting portion includes a locking hole provided in one of the back holder and the retainer, and a locking protrusion provided in the other and engaged with the locking hole,
The airbag device according to any one of claims 1 to 4, wherein the locking hole and the locking projection are provided between the outer support portion and the inflator. The airbag device according to any one of claims 1 to 5, wherein the support portion is provided with an exhaust hole penetrating the elastic connecting portion in a thickness direction.

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