Patent ID: 12257972

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A side airbag device according to embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG.1is a perspective view primarily illustrating an external shape of a vehicle seat according to the present invention, with an illustration of an airbag device (airbag module)20omitted.FIG.2is a perspective view illustrating an internal structure (seat frame) functioning as a framework of the vehicle seat illustrated inFIG.1, with an illustration of the airbag device (airbag module)20omitted herein as well.FIG.3is a schematic side surface view of the vehicle seat according to the present invention, illustrating a condition where the airbag device (airbag module)20is stowed on a side surface (near side) near a left side seat door as observed from the outside in the vehicle width direction.

As illustrated inFIG.1andFIG.2, the vehicle seat in the present embodiment, when viewed as a part, is composed of a seat cushion2of a portion in which an occupant is seated; a seat back1forming a backrest; and a headrest3connected to the upper end of the seat back1.

As illustrated inFIG.2, a seatback frame1fforming a skeleton of the seat is provided inside the seatback1, a pad16(seeFIG.4) containing a urethane foam material or the like is provided on a surface and periphery thereof, and a surface of the pad16is covered with a surface skin14(seeFIG.4) such as leather, fabric, or the like. A seating frame2fis provided on a bottom side of the seat cushion2. Similar to the seat back1, a pad including a urethane foam material or the like is provided on an upper surface and periphery thereof, and a surface of the pad is covered by the skin14(seeFIG.4) such as leather, fabric, or the like. The seating frame2fand the seatback frame1fare connected via a reclining mechanism4.

As illustrated inFIG.2, the seat back frame1fis configured into a frame shape by side frames10disposed laterally spaced apart and extending in the vertical direction, an upper frame connecting the upper ends of the side frames10, and a lower frame connecting the lower ends thereof. The headrest3is configured by providing a cushioned component outside a headrest frame.

FIG.4is a cross sectional view illustrating the structure of the vehicle seat according to the present invention, corresponding to a part of a cross section in an A1-A1direction ofFIG.3.FIG.5(A)is a cross sectional view illustrating a stowed condition of the side airbag device according to the present invention, which is an enlarged view of a part ofFIG.4.

As illustrated inFIG.4, the seat back1includes a side supporting part12which swells in the vehicle traveling direction (vehicle front) on a side part (end part) in the vehicle width direction. A urethane pad16is arranged inside the side supporting part12, and the side airbag device20is stowed in a gap of the urethane pad16. The side airbag device20includes: an airbag33that restrains an occupant when expanded and deployed; and an inflator30that supplies an expansion gas to the airbag33.

The side frame10can be molded of resin or metal and, as illustrated inFIG.4, can be formed into a U-shaped or L-shaped cross sectional shape. The inflator30is secured by a stud bolt32at the inner side of the side frame10(center side of the seat).

Seams18,22,24of the skin14of the seat back1are interwoven and connected by sewing. The seam18on the front side is cleft when the airbag is deployed. InFIG.4, reference code25indicates a door trim.

The side airbag device20according to the present invention has a bracket100that retains the airbag33in a compressed state. The bracket100has a rear region100athat covers a rear side of the airbag33in a compressed state and an inner region100bthat extends continuously forward from the rear region100abetween an inner side of the airbag33and a seat pad16.

The bracket100is molded into a seat shape from a material with a higher rigidity than a base fabric material included in the airbag33. Herein, “high rigidity” is degree of rigidity where the bracket100is sufficiently strong for retaining the airbag33in a compressed state yet can be deformed by deployment of the airbag33. The bracket100can be molded from resin, metal, or a mixed material of resin and metal. For example, an electro-galvanized steel sheet (SECC) or cold-rolled steel sheet (SPCC) at a thickness of approximately 0.5 mm can be used as a material for the bracket100.

The rear region100aof the bracket100is a structure that engages with the stud bolt32of the inflator30. Two holes are formed in the rear end portion of the bracket100, and the stud bolts32of the inflator30can be inserted into the holes to secure the bracket100.

The rear region100aand inner region100bof the bracket100are formed to closely fit to and follow an external shape of the airbag33in a compressed state. Thus, by making the bracket100closely fit to follow the shape of the airbag33in a compressed state, the airbag33can be reliably retained and the airbag device (module) can be compactly stowed.

As illustrated inFIG.5(A), a front end portion100cof the inner region100bof the bracket100extends to the vicinity of a front end33aof the airbag33in a compressed state. In this case, the airbag33can be deployed more reliably to the front along the inner region100b. Note that inFIGS.5(A), (B), and (C), each region (100a,100b,100d) of the bracket100is illustrated as a general area enclosed by a dashed line.

FIGS.5(B)and (C) are cross sectional views illustrating other Embodiments of the side airbag device according to the present invention. In the Embodiment illustrated inFIG.5(B), the front end portion100cof the inner region100bof the bracket100is a structure extending to the vicinity of a front end10aof the side frame10. In this case, the bracket100can retain the airbag33over as small of an area as possible and still guide deployment of the airbag33. If the front end portion100cof the inner region100bof the bracket100does not reach the front end10aof the side frame10, the airbag33may easily over-deploy to the inner side of the seat and slow forward deployment.

In the Embodiment illustrated inFIG.5(C), the bracket100is configured to include the outer region100dextending between the airbag33and side frame10from the rear region100a. Providing the outer region100dof the bracket100allows the airbag33to deploy forward while being guided between both the inner region100band outer region100dof the bracket100, thus ensuring more reliable control (guidance) of the forward deployment of the airbag33.

The outer region100dof the bracket100includes a first portion110facing forward (vehicle traveling direction) on the front edge portion10aof the side frame10. Thereby, a portion of the airbag33positioned more in front of the side frame10deploys reliably to the front using the first portion110as a reaction surface.

FIG.6is a schematic view illustrating a stowed condition of the side airbag device according to the present invention, observed from the rear. As illustrated inFIG.6, the width (height) of the bracket100in an up-down direction is larger than the length of the inflator30in the up-down direction. In this case, the pressure of gas discharged from an outer circumferential portion of the inflator30is supported by the rear region100aof the bracket100. If the width of the bracket100in the up-down direction is smaller than the vertical length of the inflator30in the up-down direction, a portion of the gas discharged from the inflator30directly reaches an inner surface of the airbag33, causing a portion of the airbag33to expand rearward, thereby making control of the deployment posture of the entire airbag33difficult.

As described above, the present invention is provided with the bracket100having the rear region100acovering a rear side of the airbag33in a compressed state and the inner region100bextending continuously from the rear region100ato the front between the inner side of the airbag33and the seat pad16. Therefore, when the airbag33starts to deploy, the rear region100aof the bracket100is used as a reaction surface to ensure that the airbag33deploys reliably and efficiently toward the front.

Furthermore, the presence of the inner region100bof the bracket100also facilitates forward deployment of the airbag33along the inner region100b. In other words, when the airbag100[sic] starts to deploy, the rear portion of the airbag33can be prevented from deploying rearward (or diagonally rearward). As a result, the deployment shape and deployment posture of the airbag33are favorable, and the deployment rate of the airbag33is improved.

Although the present invention has been described with reference to embodiments, the present invention is not limited in any way to these embodiments, and can be changed as appropriate within the scope of the technical idea of the present invention. For example, while a side airbag on the near side has been predominantly mentioned in the embodiments described above, use is also possible with a far side airbag (surface on the far side from a vehicle door of a vehicle seat), in very small vehicles such as a single seat vehicle (irrespective of the presence of a door, a vehicle including parts with only one seat in a single row), and the like.