Airbag module case for side impact airbag module

Abstract: A case (70) for covering a cushion and inflator of an airbag module assembly is securable by arms (74, 75, 76, 77) to the side of a vehicle seat. Two of the arms project from each opposing side edge (80, 82) of an open base (78) of a cover portion (72) of the case (70). Each opposed pair of the arms (74, 76; 75, 77) substantially encircle the airbag cushion and inflator and their distal ends (85, 89; 87, 91) overlap so that a self-fastening stud projecting from the inflator can pass through apertures (84, 86; 88, 90) provided close to the distal ends of the arms. Alternatively, each side edge (80, 82) of the cover portion (72) may have a single arm with two spaced apertures or an elongate slot for receiving two fastening studs. The or each arm (76, 77) on one side of the cover (72) includes a tear seam (92a, 92b).

Description: The present invention relates to an airbag module and, more particularly, to an airbag module case for use with a side impact airbag module that mounts on the exterior of a motor vehicle seat. An airbag module is part of an inflatable restraint system that is employed in an automobile for protecting an occupant against injury by physically restraining the occupant's body when the automobile encounters a collision. The airbag module normally includes an airbag cushion and an inflator that, once triggered by a remote collision sensor, provides the inflation gas for inflating the airbag cushion. As its name implies, a side impact airbag module protects an occupant against an impact to the side of the automobile and is normally positioned somewhere between the occupant and the side of the automobile closest to the occupant. One option for positioning a side impact airbag location which has proven advantageous is on the side of a seat back of a seat, adjacent the center pillar of the auto. This position is advantageous because the airbag is kept in the optimum firing position, adjacent the driver's upper body, as the seat back is adjusted. Currently, most seat mounted airbag modules are designed to be installed internally within the seat behind the padding and the upholstery of the seat cover. These internal installations, however, require substantial changes to the design of the seat and also require the seat assembler to handle the airbag module. Internal installations, therefore, increase the chances of module damage during assembly into the seat as well as provide difficulties in accessing the module thereafter for servicing purposes or replacement. Due to these problems and other possible seat structure design concerns, side impact airbag modules that attach to the exterior of seats and are fastened to the exterior of the seats during assembly of the automobile and not during assembly of the seat are being introduced. An airbag module case is described in EP-A-0687597 which application designates all of the countries designated in the present application. EP-A-0687597 has a filing date of 12 June 1995 and a publication date of 20 December 1995. Its content accordingly constitutes prior art for the present application for the purpose of novelty only in accordance with EPC Articles 54(3) and 56. The module includes a cover into which an inflator and airbag assembly is inserted. Two flaps, extending from the cover, are folded over each other to close the case with each of four studs, which project from the inflator, extending through holes in the two flaps. The holes are positioned substantially centrally in the flaps. Since these airbag modules will be exposed on an exterior of a seat in the passenger compartment of a motor vehicle, there is a need for an airbag module cover or case that conceals and protects the airbag module, is aesthetically pleasing and blends in with the seat as much as possible, and is easily attached to the airbag module independently of the seat. The present invention is directed to an airbag module case for use with a side impact airbag module that satisfies one or more of the above needs and to an airbag module employing such a case. In carrying out this invention, there is provided an airbag module case for use with a side impact airbag module adapted to mount to the exterior of a motor vehicle seat. The airbag module includes an airbag cushion and inflator assembly having a folded airbag cushion and an inflator connected together so that inflation gas from the inflator will inflate the airbag cushion. The airbag module also includes at least one mounting projection extending from the airbag cushion and inflator assembly that is adapted to extend into and be secured in the motor vehicle seat. The airbag module case includes an assembly cover and at least two retainer arms. The assembly cover is sized and shaped to substantially conceal and protect any exposed portions of the airbag cushion and inflator assembly of the side-impact airbag module when the airbag module is mounted to the exterior of the motor vehicle seat. The assembly cover has an open base sized to receive the airbag cushion and inflator assembly, the open base is defined by at least one edge of the assembly cover. The at least two retainer arms are opposed and extend from the edge of the assembly cover. Each retainer arm has at least one projection receiving aperture located adjacent a distal end thereof. The opposed retainer arms are sized and shaped to tightly hug the airbag cushion and inflator assembly with the distal ends of the opposed retainer arms overlapping and positioned so that the at least one mounting projection extending from the airbag cushion and inflator assembly extends through the at least one projection receiving aperture of each retainer arm to secure the airbag module case to the side-impact airbag module. The present invention, therefore, provides an airbag module cover or case that conceals and protects the airbag module, is aesthetically pleasing and blends in with the seat as much as possible, and is easily attached to the airbag module independently of the seat. The invention together with further objects, features, advantages and aspects thereof, will be more clearly understood from the following description taken in connection with the accompanying drawings. FIG. 1 is an elevational end view of an airbag module case according to the present invention shown secured to a side-impact airbag module assembly mounted to the exterior of a motor vehicle seat; FIG. 2 is an elevational side view of the airbag module case of FIG. 1 shown secured to the side-impact airbag module assembly mounted to the exterior of a motor vehicle seat; FIG. 3 is an elevational end view of the airbag module case of FIGS. 1 and 2; FIG. 4 is an elevational side view of the airbag module case of FIGS. 1 through 3; FIG. 5 is an elevational end view of another airbag module case according to the present invention; FIG. 6 is an elevational side view of the airbag module case of FIG. 5; FIG. 7 is an elevational end view of an additional airbag module case according to the present invention; and FIG. 8 is an elevational side view of the airbag module case of FIG. 7. The same reference numerals refer to the same elements throughout the various figures. Referring to FIGS. 1 through 4, the present invention is directed to an airbag module case 10 for use as part of a side impact airbag module 100 that mounts on the exterior of a motor vehicle seat 110 having an access opening 112 in a seat cover 114 and receiving means 116 within an internal structural member 117. The side impact airbag module 100 includes an airbag cushion and inflator assembly 102 having an airbag cushion 104 and an inflator 106 connected together so that inflation gas from the inflator 106 will inflate the airbag cushion 104. The airbag cushion and inflator assembly 102 is described generally as it relates to the instant invention. How an inflator 106 produces inflation gas and is actuated are both known in the art and, accordingly, are not described in detail as they do not in themselves constitute features of the present invention. As shown the airbag module 100 also has two mounting projections comprising self-fastening studs 108a,108b extending from the airbag cushion and inflator assembly 102, generally from the inflator 106, and adapted to extend into the motor vehicle seat 110 and be secured within the receiving means 116 of the internal structural member 117 to mount the airbag module to the seat. The self-fastening studs 108a,108b are also not described in detail as they do not in themselves constitute features of the present invention. However, it should be noted that the mounting projection could be provided in a forms other than mounting studs such a flat elongated mounting flange, for example, and that the studs have securing means for engaging the receiving means 116 of the structural member 117 . The airbag module case according to the present invention can be adapted for use with airbag modules having other such mounting projections without departing from its true scope. The airbag module case 10 is comprised of a suitable material such as thermoplastic polyurethane, for example, and includes an assembly cover 12, and a first retainer arm 14 and a second retainer arm 16 that are unitary with the assembly cover 12. The retainer arms 14,16 are resiliently flexible. The assembly cover 12 is sized and shaped to substantially cover, conceal and protect any exposed portions of the airbag cushion and inflator assembly 102 of the side-impact airbag module 100 when the airbag module is mounted to the exterior of the motor vehicle seat 110. As shown, the assembly cover 12 is a generally rectangular box with a generally rectangular open base 18 , but could be provided in another shape, for example oval or circular, to accommodate a different airbag cushion and inflator assembly 102. The generally rectangular open base 18 is sized and shaped to receive the airbag cushion and inflator assembly 102 and is partly defined by a first side edge 20 and an opposed second side edge 22. (The first and second side edges 20,22 are shown as broken lines as the first and second retainer arms 14,16 are unitary with the assembly cover 12. ) The first retainer arm 14 extends from the first side edge 20 and the second retainer arm 16 opposes the first retainer arm and extends from the second side edge 22 of the assembly cover 12. As shown, the retainer arms 14,16 are generally rectangular and elongated. The first retainer arm 14 defines two spaced-apart projection receiving apertures 24a,24b comprising generally circular stud-receiving holes located adjacent a distal end 26 of the first retainer arm. The second retainer arm 16 defines two spaced-apart projection receiving apertures 28a,28b comprising generally circular stud-receiving holes located adjacent a distal end 30 of the second retainer arm. The two stud-receiving holes 26a,26b of the first retainer arm 14 and the two stud-receiving holes 28a,28b of the second retainer arm 16 are spaced-apart similar to the two self-fastening studs 108a,108b extending from the airbag cushion and inflator assembly 102. As shown in FIGS. 1 and 2, the opposed retainer arms 14,16 are sized and shaped to encircle and preferably tightly hug the airbag cushion and inflator assembly 102 with the distal ends 26,30 of the opposed retainer arms overlapping and positioned so that self-fastening stud 108a extending from the airbag cushion and inflator assembly 102 will extend through stud-receiving hole 28a defined by the second retainer arm 16 and stud-receiving hole 26a defined by the first retainer arm 14, and self-fastening stud 108b extending from the airbag cushion and inflator assembly will extend through stud-receiving hole 28b defined by the second retainer arm and stud-receiving hole 26b defined by the first retainer arm to secure the airbag module case 10 to the airbag module 100. As shown, the distal end 26 of the first retainer arm 14 overlaps the distal end 30 of the second retainer arm 16, however, the distal end of the second retainer arm could alternatively overlap the distal end of the first retainer arm. The airbag module case 10 also includes a tear seam 32 which is preferably located where the second retainer arm 16 meets the second side edge 22 of the assembly cover 12. Upon inflation of the airbag cushion 104, the expanding airbag cushion will cause the tear seam 32 to break open, with the assembly cover 12 pivoting out of the way about where the first retainer arm 14 meets the first side edge 20 of the assembly cover 12, so that the airbag cushion 104 can properly inflate. The assembly cover 12 of the airbag module case 10 is adapted to substantially cover, conceal and protect the airbag cushion and inflator assembly 102, and be positioned adjacent the seat cover 114 once the airbag module 100 is mounted to the seat 110. Since the airbag module 100 is adapted to be mounted on the exterior of the seat 110, it is important that an outer surface 34 of the assembly cover 12 be aesthetically pleasing and blend in with the seat 110 as much as possible. The assembly cover 12, therefore, is provided with a class A, decorative, outer surface 34 (class refers to the quality of the surface with regards to looks, texture and other factors, with class A being the best available surface quality). The airbag module case 10 is intended to be attached to the side-impact airbag module 100 prior to mounting the airbag module to the motor vehicle seat 110. The assembly cover 12 of the airbag module case 10 is first placed over the airbag cushion and inflator assembly 102, covering substantially all of the airbag cushion 104 and at least a portion of the inflator 106. Then the retainer arms 14,16 are wrapped around the remainder of the airbag cushion and inflator assembly 102 with the distal ends 26,30 of the retainer arms being pulled over the two self-fastening studs 108a,108b so that the studs can be inserted through the stud-receiving holes 24a,24b,28a,28b defined by the retainer arms. The thermoplastic polyurethane airbag module case 10 is resiliently flexible, which allows the case 10 to fit snugly around the airbag cushion and inflator assembly 102 by allowing the retainer arms 14,16 to stretch slightly so that the studs 108a,108b can be inserted through the stud-receiving holes 24a,24b,28a,28b defined by the retainer arms and then resiliently relax back to tightly hug the airbag cushion and inflator assembly and bind against the studs so as to be retained thereon. The side impact airbag module 100 assembly is able to be mounted to the seat 110 by the automobile manufacturer during assembly of the automobile and not be required to be mounted by the seat manufacturer during assembly of the seat. The airbag module 100 is mounted to the seat 110 by simply inserting the two self- fastening studs 108a,108b through the access opening 112 in the seat cover 114 and into receiving means 116 within the seat 110. The present invention, therefore, provides an airbag module case 10 that conceals and protects the airbag module 100, is aesthetically pleasing and blends in with the seat as much as possible, and is easily attached to the airbag module 100, independently of the seat. Referring to FIGS. 5 and 6, another airbag module case 40, similar to the airbag module case 10 of FIGS. 1 through 4, is shown and includes an assembly cover 42, and a first retainer arm 44 and a second retainer arm 46 that are unitary with the assembly cover 42 . The assembly cover 42 is sized and shaped to substantially cover, conceal and protect any exposed portions of the airbag cushion and inflator assembly of the side-impact airbag module 100 when the airbag module is mounted to the exterior of the motor vehicle seat 110 (referring to the airbag module 100 and seat 110 of FIGS. 1 and 2 ). The assembly cover 42 has a generally rectangular open base 48 partly defined by a first side edge 50 and an opposed second side edge 52 . The first retainer arm 44 extends from the first side edge 50 and the second retainer arm 46 is opposite the first retainer arm and extends from the second side edge 52 of the assembly cover 42. The first retainer arm 44 defines a projection receiving aperture 54 comprising an elongated stud-receiving slot located adjacent a distal end 56 of the first retainer arm. The second retainer arm 46 defines a projection receiving aperture 58 comprising an elongated stud-receiving slot located adjacent a distal end 60 of the second retainer arm. The stud-receiving slot 54 of the first retainer arm 44 and the stud-receiving slot 58 of the second retainer arm 46 are long enough to receive both of the two self-fastening studs 108a,108b extending from the airbag module 100. The first and second retainer arms 44,46 are sized and shaped to encircle and preferably tightly hug the airbag cushion and inflator assembly 102 with the distal ends 56,60 of the retainer arms overlapping and positioned so that the two self-fastening studs 108a,108b extending from the airbag cushion and inflator assembly 102 will extend through the stud- receiving slot 54 defined by the first retainer arm and the stud-receiving slot 58 defined by the second retainer arm to secure the airbag module case 40 to the side-impact airbag module 100 . The airbag module case 40 also includes a tear seam 62 located where the second retainer arm 46 meets the second side edge 52 of the assembly cover 42. The assembly cover 42 is provided with a class A, decorative, outer surface 64. Referring to FIGS. 7 and 8, another airbag module case 70, similar to the airbag module case 10 of FIGS. 1 through 4, is shown and includes an assembly cover 72, and a first retainer arm 74, a second retainer arm 75, a third retainer arm 76 and a fourth retainer arm 77 that are unitary with the assembly cover. The assembly cover 72 is sized and shaped to substantially cover, conceal and protect any exposed portions of the airbag cushion and inflator assembly 102 of the side-impact airbag module 100 when the airbag module 100 is mounted to the exterior of the motor vehicle seat 110 (referring to the airbag module 100 and seat 110 of FIGS. 1 and 2 ). The assembly cover 72 has a generally rectangular open base 78 partly defined by a first side edge 80 and an opposed second side edge 82. The first retainer arm 74 and the second retainer arm extend from the first side edge 80, and the third retainer arm 76 and the fourth retainer arm 77 extend from the second side edge 82 of the assembly cover 72. The first retainer arm 74 defines a projection receiving aperture 84 comprising a generally circular stud-receiving hole, located adjacent a distal end 85 of the first retainer arm. The second retainer arm 75 defines a projection receiving aperture 85 comprising a generally circular stud-receiving hole, located adjacent a distal end 86 of the second retainer arm. The third retainer arm 76 defines a projection receiving aperture 88 comprising a generally circular stud-receiving hole, located adjacent a distal end 89 of the third retainer arm. The fourth retainer arm 77 defines a projection receiving aperture 90 comprising a generally circular stud-receiving hole, located adjacent a distal end 91 of the fourth retainer arm. The first retainer arm 74 and the third retainer arm 76 are opposed and are sized and shaped to encircle and preferably tightly hug the airbag cushion and inflator assembly 102 with the distal ends 85,89 overlapping and positioned so that self-fastening stud 108a extending from the airbag cushion and inflator assembly 102 will extend through the stud-receiving hole 88 defined by the third retainer arm and the stud-receiving hole 84 defined by the first retainer arm. The second retainer arm 75 and the fourth retainer arm 77 are opposed and are also sized and shaped to encircle and preferably tightly hug the airbag cushion and inflator assembly 102 with the distal ends 87,91 overlapping and positioned so that self-fastening stud 108b will extend through the stud-receiving hole 86 defined by the second retainer arm and the stud-receiving hole 90 defined by the fourth retainer arm to secure the airbag module case 70 to the side-impact airbag module 100. The airbag module case 70 also includes a first tear seam 92a located where the third retainer arm 76 meets the second side edge 80 of the assembly cover 72, and a second tear seam 92b located where the fourth retainer arm 77 meets the second side edge 82 of the assembly cover. The assembly cover 72 is provided with a class A, decorative, outer surface 94.

Claims: A thermoplastic airbag module case (10) for use with a side impact airbag module (100) adapted to mount on the exterior of a motor vehicle seat (110) and including an airbag cushion (104) and inflator assembly (102) having a folded airbag cushion (104) and an inflator (106) connected together so that inflation gas from the inflator (106) will inflate the airbag cushion (104), the airbag module case (10) comprising: an assembly cover (12) sized and shaped to substantially cover the airbag cushion and inflator assembly (102) of the side-impact airbag module when the airbag module is mounted to the exterior of the motor vehicle seat (110), the assembly cover (12) having a decorative outer surface (34) and at least one edge (20, 22) defining an open base (18) sized and shaped to receive the airbag cushion and inflator assembly (102); and at least two flexible, opposed retainer arms (14, 16) extending from the at least one edge (20, 22) of the assembly cover (12), the opposed retainer arms (14, 16) being sized and shaped to substantially encircle the airbag cushion and inflator assembly (102) with each retainer arm (14, 16) defining at least one projection receiving aperture (24a, 24b, 28a, 28b) located adjacent a distal end (26, 30) of the retainer arm (14, 16) for receiving at least one projection (108a) extending from the airbag cushion and inflator assembly (102) to secure the airbag module case (10) to the side-impact airbag module (100). The airbag module case (10) according to claim 1 further comprising a tear seam (32) located where one of the at least two retainer arms (14, 16) meets the at least one edge (20, 22) of the assembly cover (12). The airbag module case (10) according to claim 1 or 2, wherein the at least two opposed retainer arms (14, 16) of the airbag module case (10) comprise a first retainer arm (14) extending from the at least one edge (20) of the assembly cover (12) and a second retainer arm (16) extending from the at least one edge (22) of the assembly cover (12) opposite the first retainer arm (14). The airbag module case (10) according to claim 3 wherein the at least one projection receiving aperture of each retainer arm (14, 16) comprises two spaced-apart, stud-receiving openings (24a, 24b; 28a, 28b) adapted to receive two spaced-apart, self-fastening studs (108a) extending from the airbag cushion and inflator assembly (102). The airbag module case (40) according to claim 3 wherein the at least one projection receiving aperture of each retainer arm (44, 46) comprises an elongated, stud-receiving slot (54, 58) adapted to receive two spaced-apart, self-fastening studs (108a) extending from the airbag cushion and inflator assembly (102). The airbag module case (70) according to claim 1 or 2 wherein the at least two opposed retainer arms of the airbag module case comprise a first and second retainer arm (74, 75) extending from the at least one edge (50) of the assembly cover (72) and a third and fourth retainer arm (76, 77) extending from the at least one edge (82) of the assembly cover (72) opposite the first and second retainer arms (74, 75), the at least one projection receiving aperture of each retainer arm (74, 75, 76, 77) comprising a stud-receiving opening (84, 86, 88, 90) adapted to receive a self-fastening stud (108a) extending from the airbag cushion and inflator assembly (102). The airbag module case (10) according to any one of claims 1 to 4 or claim 6 wherein the projection-receiving apertures (24a, 24b, 28a, 28b) are generally circular. A side-impact airbag module (100) including a module case (10) according to any preceding claim and adapted to mount on the exterior of a motor vehicle seat (110), the airbag module (100) additionally comprising: an airbag cushion and inflator assembly (102) having a folded airbag cushion (104) and an inflator (106) connected together so that inflation gas from the inflator (106) will inflate the airbag cushion (104). The side-impact airbag module (100) according to claim 8 wherein the opposed retainer arms (14, 16) encircle the airbag cushion and inflator assembly (102) with the distal ends (26, 30) of the opposed retainer arms (14, 16) overlapping and positioned so that at least one projection (108a) extending from the airbag cushion and inflator assembly (102) extends through the at least one projection receiving aperture (24a, 24b, 28a, 28b) of both retainer arms (14, 16). The side-impact airbag module (100) according to claim 8 or 9 wherein the at least one projection comprises two spaced-apart mounting projections (108a) adapted to extend into and be secured within the motor vehicle seat (110), each mounting projection (108a) comprising a self-fastening stud. The side-impact airbag module (100) according to claim 10 when indirectly dependent on claim 4 wherein the projection receiving apertures (24a, 24b, 28a, 28b) receive the self-fastening studs (108a). The side-impact airbag module (100) according to claim 10 when indirectly dependent on claim 5 wherein each stud-receiving slot (54, 58) receives both self-fastening studs (108a). The side-impact airbag module (100) according to claim 10 when indirectly dependent on claim 6 wherein each retainer arm (74, 75, 76, 77) defines one of the projection receiving apertures (84, 86, 88, 90) which comprises a stud-receiving opening receiving one of the self-fastening studs (108a).

Inventors: PARKER DON L, SPILKER DAVID L, STOREY J KIRK, PARKER, DON L., SPILKER, DAVID L., STOREY, J. KIRK
Applicants: AUTOLIV ASP INC, AUTOLIV ASP, INC.
Application year: 1996
Main classification: B60R21
IPC codes: B60R21