JPWO2009014047A1 - Airbag device - Google Patents

Abstract

A substantially rectangular parallelepiped airbag case 3 that has an airbag 2 that restrains an occupant in the vehicle by inflating, and a substantially rectangular base plate portion 31 and that accommodates the airbag 2 in a state where it can be inflated, and a base plate portion 31 The airbag includes an inflator 4 that ejects a gas that inflates the airbag 2, and four bolts 52 that fasten the airbag 2 to the substrate portion 31 so that the airbag 2 covers the inflator 4. In the apparatus, the bolts 52 are arranged in the long side direction and the short side direction of the substrate portion 31, and the distance between the bolts 52 at both ends in the long side direction is larger than the distance between the bolts 52 at both ends in the short side direction. Configure to be longer.

Description

  The present invention relates to an airbag device that restrains an occupant in a vehicle.

  As an occupant protection device for protecting an occupant in the event of a vehicle collision, a seat belt, an airbag device, and the like have been put into practical use. An airbag device is a device that restrains an occupant wearing a seat belt in an auxiliary manner. An airbag device for a driver's seat housed in a steering wheel, an assistant housed in an instrument panel (hereinafter referred to as an instrument panel). There are various types such as a seat airbag device and a side airbag.

  A known airbag device for a passenger seat includes an airbag that restrains an occupant in the vehicle by inflating, a disk-shaped inflator that ejects inflation gas that inflates the airbag in the event of a vehicle collision, and an upper portion There is one provided with a substantially rectangular parallelepiped airbag case having a substantially rectangular opening (for example, Patent Document 1). An inflator is disposed at a substantially central portion of the substrate portion constituting the airbag case. The airbag is accommodated in an airbag case in an inflatable state, and the hem portion of the airbag is fastened to the substrate portion together with the inflator by a fastening member so that the gas outlet of the inflator is located in the airbag chamber. . In this case, the fastening member is four bolts, and the four bolts are fastened so as to be positioned at the apex of a virtual square that circumscribes the inflator.

A cylinder type is generally used as an inflator for an airbag device for a passenger seat, but a disk type inflator has less gas leakage than a cylinder type and can effectively inflate an airbag. Disc-shaped inflators are also being adopted in seat airbag devices.
JP 2006-31398 A

  When the airbag is inflated, a large pulling force acts on the hem portion of the airbag fastened to the airbag case, and the airbag may be torn or torn especially in the vicinity of the fastening bolt hole. For this reason, when the airbag is inflated, a bolt hole is provided at the apex of a virtual square that circumscribes the inflator so that a tensile force is uniformly applied to the hem portion of the airbag, and the bolt and the airbag are inserted by the bolt inserted into the bolt hole. An inflator is fastened to the substrate portion. Further, the hem portion is reinforced by overlapping and sewing a plurality of reinforcing cloths. However, at present, a large number of reinforcing cloths must be stacked and sewn, which requires excessive fabric material costs and manufacturing man-hours, and a simpler method for improving the strength of the airbag has been desired.

  The inventor of the present application pays attention to the fact that the tensile force applied to the hem portion of the airbag is larger on the long side of the substrate portion than on the short side, and the long side of the substrate portion of the hem portion of the airbag. The idea is that the tensile strength of the airbag can be improved by making the area of the portion to be fastened fastened to be larger than the area of the portion to be fastened fastened to the short side.

  The present invention has been made in view of such an idea, and the distance between the fastening members at both ends in the longitudinal direction of the substrate portion constituting the airbag case is set at both ends in the cross direction intersecting with the longitudinal direction of the substrate portion. Providing an airbag device capable of reducing the cost of fabric material and the number of manufacturing steps with a simple configuration and improving the tensile strength of the airbag by being configured to be longer than the distance between certain fastening members. The purpose is to do.

  An airbag device according to a first aspect of the present invention includes an airbag that restrains an occupant in a vehicle by inflating, and an airbag case that has a base portion that is long in one direction and accommodates the airbag in an inflatable state. And an inflator that ejects a gas that inflates the airbag, and at least three fastening members that fasten the airbag and the inflator to the base plate portion, wherein the fastening member includes: The distance between the fastening members that are arranged in the longitudinal direction of the substrate portion and the intersecting direction intersecting the longitudinal direction and that are at both ends of the longitudinal direction are longer than the distance between the fastening members that are at both ends of the intersecting direction. It is characterized by that.

  In the airbag device according to the second aspect of the present invention, the substrate portion is substantially rectangular, and the fastening members are arranged so that the long side direction and the short side direction are positioned at the vertices of the rectangle that substantially coincide with the substrate portion, respectively. It is a bolt of a book.

  The airbag device according to a third aspect of the invention is characterized in that the inflator has a disc shape, and the distance between the fastening members at both ends in the cross direction is shorter than the diameter of the inflator.

  The airbag apparatus according to a fourth aspect of the invention is characterized in that the airbag case is arranged inside an instrument panel of a passenger seat.

  The airbag device according to a fifth aspect of the invention is characterized in that the airbag case is arranged so that the crossing direction of the base plate portion is a traveling direction of the vehicle.

In the first invention, the second invention, and the fourth invention, the area of the portion to be fastened of the airbag fastened by the fastening member is the cross-direction portion where the longitudinal portion of the base plate crosses in the longitudinal direction. Therefore, the tensile strength when the airbag is inflated is greater in the longitudinal direction portion than in the cross direction portion. In addition, a longitudinal direction part means the to-be-fastened part along the longitudinal direction of a board | substrate part, and a cross direction part means the to-be-fastened part along a cross direction. On the other hand, when the airbag is inflated, the portion to be fastened of the airbag accommodated in the airbag case having a long substrate portion in one direction is applied with a larger pulling force in the longitudinal direction portion than in the cross direction portion. It is estimated that. Therefore, compared with the case where the distance between the fastening members at both ends in the longitudinal direction is equal to the distance between the fastening members at both ends in the cross direction, the strength of the fastened portion of the airbag is relatively large.
In particular, in the second invention, since the area of the fastened portion of the airbag is larger in the long side direction portion of the substantially rectangular substrate portion than in the short side direction portion, the tensile strength of the airbag is the long side direction portion. Is larger than the short side. Therefore, compared with the case where the distance between the fastening members at both ends in the long side direction of the board portion is equal to the distance between the fastening members at both ends in the short side direction, the strength of the fastened portion of the airbag is relatively large.
In addition, the rectangle described in the claims, that is, the rectangle whose long side direction and short side direction substantially coincide with the substrate portion is a virtual quadrangle. It suffices if the long side of the rectangle and the long side of the substrate portion coincide, and the short side of the rectangle and the short side of the substrate portion coincide, and the length of each side of the rectangle is not limited. That is, the dimensions and aspect ratio of the rectangle may be different from the dimensions and aspect ratio of the substrate portion.

  In the third and fourth inventions, the distance between the fastening members at both ends in the cross direction of the substrate portion is shorter than the diameter of the disk-shaped inflator. Therefore, the dimension in the cross direction of the airbag case, for example, the dimension in the short side direction of the substantially rectangular substrate portion is smaller than that of the conventional airbag apparatus.

  In the fifth aspect of the invention, the crossing direction of the substrate portions constituting the airbag case is arranged so as to be the traveling direction of the vehicle. Therefore, the degree of freedom of arrangement of the airbag case in the traveling direction of the vehicle is higher than in the case where the airbag case is arranged in another posture.

  In the first invention, the second invention, and the fourth invention, it is possible to reduce the cost of the fabric material and the number of manufacturing steps with a simple configuration, and to improve the tensile strength of the airbag.

  In the third and fourth aspects of the invention, the distance between the fastening members at both ends in the cross direction of the base plate portion is made shorter than the diameter of the disc-shaped inflator, thereby pulling the airbag. The strength can be improved, and the cross-sectional dimension of the substrate portion can be reduced as compared with the conventional airbag apparatus.

  In the fifth invention, the degree of freedom in arrangement in the traveling direction of the vehicle can be improved. Moreover, the dimension in the said advancing direction of the door body which covers an airbag can be made small. By improving the degree of freedom in arranging the airbag case and reducing the size of the door body, the airbag device can be placed closer to the front of the passenger seat, and the door body that covers the airbag when the airbag is deployed is out. It is possible to prevent collision with the head of an occupant in an out-of-position (OOP: Out Of Position) state, for example, an occupant extremely positioned on the airbag device side. In addition, it is possible to prevent a situation in which the opened door body collides with the windshield and rebounds to block the opening of the airbag case, thereby hindering the expansion of the airbag.

1 is a schematic longitudinal sectional view illustrating an airbag device for a passenger seat according to an embodiment of the present invention. It is a typical perspective view of an airbag apparatus. It is a typical exploded perspective view of an airbag device. It is a cross-sectional view of the airbag device viewed from above. It is a typical back view of an airbag case. It is a typical back view of an inflator. It is explanatory drawing which shows the effect by the improvement of the arrangement | positioning freedom degree of an airbag apparatus and size reduction of a door body. It is explanatory drawing which shows the other effect by the improvement of the arrangement | positioning freedom degree of an airbag apparatus and size reduction of a door body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,101 Airbag apparatus 2 Airbag 3 Airbag case 4 Inflator 5 Retainer ring 6 Airbag cover 7 Nut 31 Board | substrate part 35,45 Bolt hole 22 Bolt insertion hole 52 Bolt (fastening member)
61,161 Door A Instrument panel (instrument panel)

Hereinafter, the present invention will be described in detail with reference to the drawings illustrating the embodiments.
FIG. 1 is a schematic longitudinal sectional view illustrating an airbag device for a passenger seat according to an embodiment of the present invention, FIG. 2 is a schematic perspective view of the airbag device 1 shown in FIG. 1, and FIG. 4 is a schematic exploded perspective view of the bag device 1, and FIG. 4 is a cross-sectional view of the airbag device 1 viewed from above. In the figure, 1 is an example of an airbag apparatus according to an embodiment of the present invention, and is mounted in an opening B formed in an instrument panel A in front of a passenger seat. The airbag device 1 includes an airbag 2 that restrains an occupant in the vehicle by inflating, a substantially rectangular parallelepiped airbag case 3 that accommodates the airbag 2 in an inflatable state, and a gas that inflates the airbag 2. A disc-type inflator 4, a retainer ring 5 for holding the airbag 2 in the airbag case 3, and an airbag cover 6 covering the opening B of the instrument panel A.

  The instrument panel A is composed of a synthetic resin plate-like member disposed along the vehicle width direction at the lower edge of the front windshield (not shown) in front of the passenger seat, and normally the plate-like portion is a front horizontal plate portion. The rear curved plate portion is curved so as to be inclined toward the passenger seat side. At an appropriate location of the instrument panel A, an opening B having a substantially rectangular shape that is opened obliquely upward on the passenger seat side is formed.

The airbag cover 6 is made of a synthetic resin having elasticity, and has a door body 61 that has a substantially rectangular plate shape that closes the opening B of the instrument panel A, and is suspended downward from the rear surface of the long side portion of the door body 61. The airbag case 3 includes rectangular attachment walls 62 and 62 to which the airbag case 3 is fitted and attached from below.
A thin breaking groove 61 a that is broken by the expansion of the airbag 2 is formed on the rear surface of the substantially central portion in the front-rear direction of the door body 61 over both lateral ends. In addition, thin hinge portions 61b, 61b are formed on each long side portion of the door body 61, and the front half of the door body 61 opens forward and the rear half opens rearward when the breaking groove 61a breaks. ing.
A plurality of oblong retaining holes 62a,... For attaching the airbag case 3 to the airbag cover 6 are juxtaposed in the lateral direction on the attachment walls 62, 62, respectively.

  FIG. 5 is a schematic back view of the airbag case 3. The airbag case 3 is formed of metal or reinforced plastic, sometimes fabric, etc., to prevent deformation of the airbag 2 due to inflation. In the example of the present embodiment, the airbag case 3 is made of metal, and includes a substantially rectangular substrate portion 31 and side walls 32, 32, 33, and 33 that are provided substantially perpendicularly to the substrate portion 31. The upper ends of the side walls 32, 32, 33, 33 constitute a substantially rectangular opening 37.

  A circular insertion hole 34 through which the inflator 4 is inserted from below is formed at the center of the substrate portion 31, and four pieces are provided around the insertion hole 34 to fasten the inflator 4 and the airbag 2 to the airbag case 3. Bolt holes 35a, 35b, 35c, 35d (hereinafter referred to as bolt holes 35) are arranged in parallel in the long side direction (longitudinal direction) and the short side direction (crossing direction) of the substrate portion 31. More specifically, the distances between the bolt holes 35a and 35b arranged in the long side direction of the board part 31 and the bolt holes 35c and 35d are set to be between the bolt holes 35a and 35c arranged in the short side direction of the board part 31 and the bolt holes 35b. The distance between the bolt holes 35a and 35c and the distance between the bolt holes 35b and 35d arranged in the short side direction is shorter than the diameter of the insertion hole 34.

  On the side of the opening 37 of the side wall 32 provided on the long side in front of the substrate portion 31, five attachment claws 36 for attaching the airbag case 3 by being hooked in the retaining holes 62a,. Are arranged side by side in the longitudinal direction. The mounting claws 36 are composed of a rectangular piece extending outward in the short side direction from the open end side of the side wall 32, and a hook-like hooking piece formed by bending the tip of the rectangular piece downward. Yes. Similarly, four attachment claws 36,... Are arranged in the longitudinal direction on the side wall 32 provided on the long side behind the substrate portion 31, and the airbag case 3 has a short side direction of the substrate portion 31. The attachment claws 36 are attached to the attachment wall 62 by engaging the attachment claws 36 with the engagement holes 62a in a posture that substantially coincides with the traveling direction of the vehicle.

FIG. 6 is a schematic back view of the inflator 4. The inflator 4 is a disk type and includes a disk-shaped portion 41 and a flange 42 provided on the peripheral wall of the disk-shaped portion 41. The disc-type inflator 4 has less gas leakage than the cylinder-type inflator and can inflate the airbag 2 more effectively.
The peripheral wall of the disk-shaped portion 41 is provided with a plurality of gas ejection ports 43 that eject gas for inflating the airbag 2 radially outward. The gas outlet 43 is configured to eject gas at least on both sides in the long side direction and on both sides in the short side direction of the airbag case 3.
The disc-shaped portion 41 is hollow and contains an electric ignition device 44, an ignition agent (not shown), a gas generating agent, a filter, and the like inside. When the collision signal output from the control unit (not shown) is input, the electric ignition device 44 burns the gas generating agent using the ignition agent to generate a gas for inflating the airbag. The gas generated by the combustion is cooled by passing through the filter, dust generated by the combustion is removed, and the gas is ejected from the gas outlet 43 into the airbag 2.
The flange 42 has a substantially annular shape, and the flange 42 is formed with four bolt holes 45a, 45b, 45c, 45d (hereinafter referred to as bolt holes 45) corresponding to the bolt holes 35 provided in the airbag case 3. ing.

  As shown in FIG. 3, the airbag 2 is made of synthetic fiber, and is formed in a fastened portion 21 to be fastened to the airbag case 3 and the fastened portion 21, and the disc-like portion 41 of the inflator 4 is inserted therethrough. And is sewn so as to have a substantially quadrangular pyramid shape with the inflator 4 side as a vertex when the inflation is completed. The fastened portion 21 of the airbag 2 is sewed with a plurality of reinforcing cloths to improve the tensile strength, and four bolt insertion holes 22a, 22b, 22c corresponding to the bolt holes 35 of the airbag case 3 are sewn. , 22d (hereinafter referred to as bolt insertion hole 22).

The retainer ring 5 includes a substantially elliptical plate-like holding plate 51 that is disposed inside the airbag 2 and holds the fastened portion 21 to the airbag case 3. The holding plate 51 has a hole portion through which the disk-like portion 41 of the inflator 4 is inserted at a substantially central portion. Further, the holding plate 51 has four bolts 52a, 52b, 52c, 52d as four fastening members protruding from the holding plate 51 on the side of the airbag case 3 so as to correspond to the bolt holes 35 of the airbag case 3. (Hereinafter, referred to as a bolt 52).
More specifically, the distances between the bolts 52a and 52b arranged in the long side direction of the substrate portion 31 and the bolts 52c and 52d are set such that the distances between the bolts 52a and 52c arranged in the short side direction of the substrate portion 31 and between the bolts 52b and 52d. Long compared to the distance. In this case, the distance between the bolts 52a and 52c arranged in the short side direction and the distance between the bolts 52b and 52d may be provided to be shorter than the diameter of the insertion hole 34.
The bolt 52 of the retainer ring 5 arranged inside the airbag 2 is inserted into the bolt insertion hole 22 of the airbag 2, the airbag case 3 and the bolt holes 35 and 45 of the inflator 4, and is fixed to the nut 7. The fastened portion 21 of the airbag 2 is held between the retainer ring 5 and the airbag case 3, and the airbag 2 and the inflator 4 are fastened to the airbag case 3.

  The inflator 4 having the bolt hole 45 in the flange portion 42 is provided from the outside of the airbag 2 as shown in FIG. 3, and the retainer ring 5 having a bolt 52, for example, a stud bolt, is provided inside the airbag 2. However, the flange 42 of the inflator 4 may be provided with a stud bolt. In this case, the inflator 4 is provided inside the airbag instead of the retainer ring 5. When the stud 42 is provided with the stud bolt, the bolt hole 45 is not necessary, but the stud bolt may be configured to be press-fitted into the bolt hole 45 of the collar 42.

  In the airbag device 1 for a passenger seat configured as described above, the area of the portion effective for holding the airbag 2 of the fastened portion 21 of the airbag 2 is long in the distance between the bolts 52. Since the region extending on the long side is larger than the region extending on the short side, the strength of the hem portion of the airbag 2 in the fastened portion 21 is greater in the long side direction than in the short side direction. large. Therefore, the airbag 2 is accommodated in the substantially rectangular parallelepiped airbag case 3, and the tensile force applied to the fastened portion 21 when the airbag 2 is inflated is larger in the long side direction than in the short side direction. In the configuration of the form, the tensile strength of the fastened portion 21 can be improved with a simple configuration, and the cost of the fabric material and the number of manufacturing steps can be reduced.

Since the distance between the bolts 52a and 52c arranged in the short side direction can be made smaller than the diameter of the disk-shaped portion 41 of the inflator 4, the dimension in the short side direction of the airbag case 3 is made smaller than that of the conventional airbag device. be able to.
It is possible to reduce the weight by reducing the size of the airbag case 3.

The airbag device 1 is arranged with the airbag case 3 so that the width of the airbag case 3 in the short side direction is shorter than that of the conventional airbag device 1 and the short side direction substantially coincides with the traveling direction of the vehicle. Therefore, the degree of freedom of arrangement of the airbag device 1 in the front-rear direction can be improved.
Due to the downsizing of the airbag device 1, the door body 61 can also be downsized, and the injury of the occupant in the out-of-position situation can be avoided.

  FIG. 7 is an explanatory diagram showing the effect of improving the degree of freedom of arrangement of the airbag device 1 and reducing the size of the door body 61. FIG. 7A shows a state in which the airbag apparatus 1 according to the present invention is arranged inside the instrument panel A, and FIG. 7B shows a state in which the conventional airbag apparatus 8 is arranged inside the instrument panel A. ing. The semicircle shown with the broken line has shown the locus | trajectory which the front-end | tip part of the door body 61 draws when the airbag 2 is inflated. Further, the collision dummies D and D in two kinds of out-of-position situations are indicated by solid lines and two-dot chain lines, respectively. Since the airbag apparatus 1 according to the present invention has a high degree of freedom in arrangement in the front-rear direction, the airbag case 3 can be arranged more forward than the conventional airbag apparatus 8. As shown in FIG. 7B, when the airbag device 8 is arranged near the passenger seat due to the restriction of the degree of freedom of arrangement, the door body 81 opened by the inflation of the airbag is placed on the head of the occupant in the out-of-position state. Although there is a danger of collision, the collision of the door body 61 can be avoided by arranging the airbag device 1 further forward as shown in FIG.

FIG. 8 is an explanatory view showing another effect of the improvement in the degree of freedom of arrangement of the airbag device 101 and the downsizing of the door body 161. FIG. 8A shows a state in which the airbag apparatus 101 according to the present invention is arranged inside the instrument panel A, and FIG. 8B shows a state in which the conventional airbag apparatus 9 is arranged inside the instrument panel A. ing. The airbag apparatus 101 according to the present invention shown in FIG. 8A is different from the airbag apparatus 101 only in that one door body 161 is a single opening that opens forward when the airbag 2 is inflated. is there. As shown in FIG. 8B, the conventional airbag device 9 also has a single-open configuration in which one door 91 opens when the airbag 2 is inflated.
As shown in FIG. 8B, when the longitudinal dimension of the door body 91 is large, when the airbag device 9 is arranged closer to the passenger seat, the opened door body 91 collides with the head of an occupant in an out-of-position situation. If the airbag device 9 is disposed closer to the front, the opened door body 91 may collide with the front windshield C and bounce off, thereby hindering the expansion of the airbag 2.
As shown in FIG. 8A, the airbag device 101 according to the present invention has a smaller door body 161 and a higher degree of freedom in arrangement in the front-rear direction than the conventional airbag device 9. Therefore, the airbag apparatus 101 can be disposed on the instrument panel A so that the door 161 does not collide with the head of an occupant who is out-of-position and does not collide with the windshield C.

  The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims. That is, the airbag device described above is a preferred example of the present invention, and other embodiments can be implemented or performed by various methods. As long as there is no statement of the meaning limited in this specification, this invention is not restrict | limited to the shape of the detailed components shown in the accompanying drawing, a magnitude | size, a structure arrangement | positioning, etc. Expressions and terms used in the present specification are for the purpose of explanation, and are not limited thereto unless otherwise specified. For example, the airbag device for the passenger seat has been described in the embodiment, but the present invention may be applied to an airbag device for a driver seat.

  In the embodiment, the case where the airbag is fastened to the airbag case with four bolts has been described. However, the airbag may be fastened with three or five or more bolts.

Claims (5)

An air bag that restrains an occupant in the vehicle by inflating, an air bag case that has a board portion that is long in one direction and that can be inflated, and a gas that inflates the air bag. An airbag device comprising: an inflator to be ejected; and at least the airbag and three or more fastening members that fasten the inflator to the substrate portion,
The fastening members are arranged in a longitudinal direction of the substrate portion and a crossing direction crossing the longitudinal direction, and a distance between the fastening members at both ends in the longitudinal direction is between the fastening members at both ends in the crossing direction. An airbag device characterized by being longer than the distance. The substrate portion is substantially rectangular,
2. The airbag device according to claim 1, wherein the fastening member is four bolts arranged so that a long side direction and a short side direction are positioned at respective vertices of a rectangle that substantially coincides with the substrate portion. . The inflator has a disk shape,
The airbag apparatus according to claim 1 or 2, wherein a distance between the fastening members at both ends in the cross direction is shorter than a diameter of the inflator.   The airbag device according to any one of claims 1 to 3, wherein the airbag case is arranged inside an instrument panel of a passenger seat. The airbag case is
The airbag apparatus according to claim 4, wherein the crossing direction of the substrate portion is arranged to be a traveling direction of a vehicle.

Images