Airbag device and method for manufacturing the same

Abstract

The present invention aims to provide an airbag device that can be compactly stored. The present invention is an airbag device stored in a vehicle seat, comprising: an airbag cushion that restrains an occupant by expanding and deploying; an inflator that is arranged on the inner side of a vehicle seat frame and supplies inflation gas to the airbag cushion; and a cover member that is formed of a ductile material that melts and shrinks by heating and pressurizing and is used to hold the airbag cushion. The airbag cushion includes a rear chamber portion that stores the inflator, and a front chamber portion that extends forward from the rear chamber portion and is arranged on the outer side of the seat frame when stored. The cover member is configured to compress and hold the portion of the airbag cushion by heating and pressurizing at least the area corresponding to the front chamber portion of the airbag cushion.

Description

Technical Field

[0001] The present invention relates to a safety airbag device mounted on a vehicle seat and a method for manufacturing the same. Background Art

[0002] As is known to all, one or more airbags are provided on a vehicle to protect passengers in the event of an accident. There are various forms of airbags, for example, a so-called driver airbag that expands and deploys near the center of the steering wheel of a car to protect the driver, a curtain airbag that expands downward from the inner side of a car window to protect passengers in the event of a lateral impact, rollover, or rollover of the vehicle, and a side airbag that is stored in a side support portion of a seat and expands and deploys between the passenger and the side panel to protect passengers in the event of a lateral impact of the vehicle. The present invention mainly relates to a side airbag device.

[0003] Since the side airbag device is stored inside the side support portion of the seat, there are many restrictions on the shape and size, and it is necessary to package it compactly. Therefore, there are methods in the prior art documents such as compressing the airbag by folding or rolling it, and installing it on the seat frame in a state where the airbag is covered with a soft cover. In this case, when the airbag begins to expand and deploy due to the inflation gas, the cover breaks and the airbag is greatly deployed to the outside.

[0004] However, if the compressed airbag is simply held by a cover as in the conventional method, the airbag cannot be made sufficiently compact, and further compactness is required.

[0005] In particular, when the inflator is disposed inside the seat frame and most of the compressed airbag is disposed outside the seat frame, it is difficult to store the airbag compactly.

[0006] In addition, in the proposed method, a hard plastic cover is provided around the folded or rolled airbag, but the use of the hard cover not only significantly increases the cost and weight of the airbag unit, but also fails to sufficiently reduce the volume of the packaged airbag. Summary of the invention

[0007] The present invention has been made in view of the above-mentioned situation, and an object of the present invention is to provide an airbag device that can be compactly stored in a vehicle seat.

[0008] Another object of the present invention is to provide a method for manufacturing an airbag device that can be compactly stored in a vehicle seat.

[0009] Solutions to the problem

[0010] (First Form)

[0011] In order to achieve the above-mentioned object, the first form of the present invention is an airbag device housed in a vehicle seat, comprising: an airbag cushion that restrains an occupant by expanding and deploying; an inflator that is arranged on the inner side of a vehicle seat frame and supplies inflation gas to the airbag cushion; and a cover member that is formed of a ductile material that melts and shrinks by heating and pressurizing and that holds the airbag cushion. The airbag cushion includes a rear chamber portion that houses the inflator and a front chamber portion that extends forward from the rear chamber portion and is arranged on the outer side of the seat frame when housed. Furthermore, the cover member is configured to compress and hold the airbag cushion by heating and pressurizing at least a region corresponding to the front chamber portion of the airbag cushion.

[0012] Here, "heating and pressurizing" means applying pressure to the cover member holding the airbag cushion in a heated state using a mold or the like. In addition, "ductile material" means a material having a material component that imparts mobility or elasticity to the fabric fiber, or a material having a fiber structure with mobility or elasticity. Due to the mobility or elasticity of the material, the ductile fabric will fit snugly on the inner surface of the metal mold cavity during the heating and pressurizing process.

[0013] As described above, in the present invention, the cover member for holding the airbag cushion is compressed and held by heating and pressurizing at least the area corresponding to the front chamber portion of the airbag cushion. That is, the cover member is held in a state where the portion occupying the main part of the airbag cushion and arranged on the outside is compressed by the cover member. At this time, the cover member that is heated and pressurized melts and shrinks, so that the hardness of this portion of the cover member becomes higher than that of other portions, and the shape retention performance is improved. On the other hand, since the rear chamber portion that accommodates the inflator is not compressed via the cover member, it is maintained in a relatively soft state and is easier to bend.

[0014] The front chamber portion of the airbag cushion may be stored in a rolled or folded form.

[0015] When stored, the airbag cushion may have a curved portion between the front chamber portion and the rear chamber portion, the curved portion being bent at a front edge portion of the seat frame.

[0016] Preferably, a portion of the cover member corresponding to the bent portion of the airbag cushion is not heated or pressurized. Thus, the softness of the bent portion can be ensured, the airbag cushion can be bent more easily, and the airbag cushion can be stored in a state of being in close contact with the seat frame.

[0017] The cover member is formed of a ductile cloth material containing a plurality of polymer fibers, and can maintain a predetermined shape by welding at least a portion of the fibers to each other.

[0018] The cover member may be configured to include: a front cover region that at least surrounds the front chamber portion of the airbag cushion; and a rear cover region that extends rearward of the front cover region and at least covers a portion of the rear chamber portion of the airbag cushion. Furthermore, the rear cover region may be formed to include a first rear edge portion located inside the rear end of the cover member and a second rear edge portion located outside.

[0019] Preferably, the inflator is fixed to the seat frame by a stud, and a tab connected to the stud penetrating the outside of the seat frame is provided at an end of the front cover region of the cover member.

[0020] The joint is heated and pressurized to increase its rigidity and can be connected to the stud more easily.

[0021] Both the first rear edge portion and the second rear edge portion of the cover member are connected to the rear chamber portion of the airbag cushion by sewing in a breakable manner.

[0022] In this case, when the airbag cushion starts to expand and deploy, the sewn portion is broken, and the cover member releases the ability to hold the compressed airbag cushion.

[0023] The second rear edge portion of the cover member may be fixed to the stud on the inner side of the seat frame.

[0024] In this case, the mounting position of the airbag module including the airbag cushion, the cover member, and the inflator will not be easily displaced, and a desired posture and position can be maintained relatively easily.

[0025] The first rear edge portion of the cover member may be connected to the rear chamber portion of the airbag cushion by sewing.

[0026] A fragile slit may be formed in the first rear edge portion of the cover member near the sewing.

[0027] In this case, when the airbag cushion starts to deploy, interference with the airbag cushion can be suppressed to a minimum by accurately pulling the cover member apart.

[0028] Both the first rear edge portion and the second rear edge portion may be configured to be fixed to the stud so that the rear cover region of the cover member surrounds the rear chamber portion of the airbag cushion.

[0029] In this case, the installation position and installation posture of the airbag assembly including the airbag cushion, the cover member, and the inflator can be maintained in a more optimal state.

[0030] A slit may be formed in a portion of the rear cover region of the cover member.

[0031] (Second Form)

[0032] The second form of the present invention is a method for manufacturing an airbag device housed in a vehicle seat, comprising: a step of housing an inflator in a rear chamber portion of an airbag cushion; a step of compressing the front chamber portion of the airbag cushion into a rolled or folded state; a step of configuring a cover member formed of a ductile material that melts and shrinks by heating and pressurizing to cover at least a portion of the front chamber portion and the rear chamber portion, thereby forming a first intermediate package; a step of heating and pressurizing a portion of the cover member to further compress the front chamber portion of the airbag cushion to form a second intermediate package; a step of fixing the inflator to the inside of the seat frame; a step of bending the front chamber portion and the rear chamber portion of the airbag cushion to configure the front chamber portion on the outside of the seat frame; and a step of connecting the end of the cover member to the seat frame.

[0033] In the specification and claims of the present application, when the occupant is seated in a normal posture, the direction the occupant is facing (the direction of travel of the vehicle) is referred to as "front", the opposite direction is referred to as "rear", and the coordinate axes are referred to as "front-rear direction". In addition, when the occupant is seated in a normal posture, the right side of the occupant is referred to as "right direction", the left side of the occupant is referred to as "left direction", and the coordinate axes are referred to as "left-right direction". In the left-right direction, the area closer to the occupant side than the seat side frame is referred to as "inside", and the area opposite to the occupant when viewed from the side frame is referred to as "outside". Furthermore, when the occupant is seated in a normal posture, the direction of the occupant's head is referred to as "upward", the direction of the occupant's waist is referred to as "downward", and the coordinate axes are referred to as "upward and downward direction". BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a perspective view showing the main external shape of the vehicle seat according to the present invention, and the side airbag device is omitted from the illustration.

[0035] Figure 2 To express as Figure 1 The illustrated perspective view is of an internal structure (seat frame) in which a framework of a vehicle seat functions, and illustration of a side airbag device is omitted.

[0036] Figure 3 This is a schematic side view of the vehicle seat according to the present invention, schematically showing a side airbag device in a stored state as viewed from the outside in the vehicle width direction.

[0037] Figure 4This is a schematic side view of the vehicle seat according to the present invention, showing a state in which the airbag cushion is deployed as viewed from the outside in the vehicle width direction.

[0038] Figure 5 1 is a cross-sectional view showing a vehicle seat structure according to an embodiment of the present invention, corresponding to Figure 3 A portion of the cross section along the A1-A1 direction.

[0039] Figure 6 (A) Figure 6 (B) is a plan view showing the positional relationship and structure between the cover member and the airbag cushion according to the first embodiment, and (A) and (B) are shown with the front and back thereof reversed.

[0040] Figure 7 This is a schematic diagram showing the structure of fibers used in the production of the cover member.

[0041] Figure 8 1 and 2 are cross-sectional views showing the structures of the airbag cushion and the cover member according to the first embodiment, wherein (A) shows a state before the heating and pressing step, and (B) shows a state after the heating and pressing step.

[0042] Fig. 9 It is a cross-sectional view showing a state where the airbag device according to the first embodiment is mounted on a seat frame.

[0043] Fig.10 This is a cross-sectional view showing the structure of an airbag cushion and a cover member according to a second embodiment of the present invention, showing a state before a heating and pressurizing step.

[0044] Fig.11 It is a cross-sectional view showing a state where the airbag device according to the second embodiment is mounted on a seat frame.

[0045] Fig.12 This is a cross-sectional view showing the structure of an airbag cushion and a cover member according to a third embodiment of the present invention, showing a state before a heating and pressurizing step.

[0046] Fig.13 It is a cross-sectional view showing a state where the airbag device according to the third embodiment is mounted on a seat frame.

[0047] Fig.14 This is a cross-sectional view showing the structure of an airbag cushion and a cover member according to a fourth embodiment of the present invention, showing a state before a heating and pressurizing step.

[0048] Fig.15 It is a cross-sectional view showing a state where the airbag device according to the fourth embodiment is mounted on a seat frame. DETAILED DESCRIPTION

[0049] Hereinafter, an airbag device according to an embodiment of the present invention will be described with reference to the drawings.

[0050] Figure 1 This is a perspective view showing the main external shape of the vehicle seat according to the present invention, and illustration of the airbag device (airbag module) 20 is omitted. Figure 2 To express as Figure 1 The illustrated perspective view is of an internal structure (seat frame) in which the framework of the vehicle seat functions, and the airbag device (airbag module) 20 is also omitted from illustration. Figure 3 1 is a schematic side view of the vehicle seat according to the present invention, showing a state in which the airbag device (airbag module) 20 is stored on the side surface (near side) of the left seat close to the door, as viewed from the outside in the vehicle width direction. Figure 4 This is a schematic side view of the vehicle seat according to the present invention, showing a state in which the airbag cushion is deployed as viewed from the outside in the vehicle width direction.

[0051] When the vehicle seat involved in this embodiment is viewed as a part, Figure 1 and Figure 2 The structure shown includes a seat cushion 2 which is a seat portion for an occupant, a backrest 1 which forms a backrest, and a headrest 3 connected to the upper end of the backrest 1 .

[0052] like Figure 2 As shown, a backrest frame 1f forming a skeleton is provided inside the backrest 1, and a cushion 16 made of a polyurethane foam material or the like is provided on its surface and around it (see Figure 5 ), the surface of the cushion 16 is covered with a leather, fabric or other surface 14. A seat frame 2f is arranged at the bottom side of the seat cushion 2, and a cushion made of polyurethane foam material is arranged on and around it, similarly to the backrest 1. The surface of the cushion is covered with a leather, fabric or other surface 14 ( Figure 5 The seat frame 2f and the backrest frame 1f are connected via a reclining mechanism 4.

[0053] like Figure 2 As shown, the backrest frame 1f is formed into a frame shape by side frames 10 separated and extending in the vertical direction, an upper frame connecting the upper ends of the side frames 10, and a lower frame connecting the lower ends. The headrest 3 is formed by providing a cushioning member outside the headrest frame.

[0054] (First embodiment)

[0055] Figure 5 2 is a cross-sectional view showing a vehicle seat structure according to the present invention, and Figure 3 The side frame 10 is formed of resin or metal, such as Figure 5As shown, the cross-sectional shape may be an L-shape or a U-shape. Also, the airbag module (side airbag device) 20 is fixed to the side frame 10 .

[0056] like Figure 5 As shown, the backrest 1 has a side support portion 12 that bulges out in the vehicle travel direction (vehicle front) at the side portion (end portion) in the vehicle width direction. A polyurethane pad 16 is arranged inside the side support portion 12, and a side airbag device 20 is accommodated in the gap of the polyurethane pad 16. The side airbag device 20 includes: an airbag cushion 33 that restrains the occupant by expanding and deploying; and an inflator 30 that supplies inflation gas to the airbag cushion 33. The inflator 30 has a stud 32 that penetrates from the inside to the outside of the seat frame 10.

[0057] The seams 18, 22, 24 of the skin 14 of the backrest 1 are woven into the inside and connected by sewing. In addition, the front seam 18 is torn when the airbag cushion 33 is inflated and deployed.

[0058] The airbag cushion 33 can be manufactured by sewing the peripheries of two sheets of flexible material, or by folding a sheet in half, overlapping two layers, and sewing the peripheries. Alternatively, the vertical yarns and horizontal yarns forming two layers can be woven at selected portions to form a bag-like shape with the fabric structure of the two sheets, which is the so-called "OPW One-Piece Woven" technology.

[0059] The cloth used to make the airbag cushion 33 is preferably a cloth having plasticity, for example, a cloth woven from vertical and horizontal yarns of polyamide fibers can be used. In addition, a thermoplastic material can also be applied to a non-plastic cloth.

[0060] The airbag cushion 33 has an opening (not shown) for inserting the cylindrical inflator 30 into the airbag cushion 33. One end of the inflator 30 is exposed from the airbag cushion 33, and a control cable for supplying an ignition signal to the portion is connected. A pair of studs 32 extending outward are provided on the outer surface of the inflator 30, and pass through holes formed in the airbag cushion 33 to be fixed to the seat frame 10.

[0061] like Figure 5 As shown, the cover member 50 of the airbag device 20 according to the present embodiment is formed of a ductile material that melts and shrinks by heating and pressurizing, and is used to hold the airbag cushion 33 .

[0062] Figure 6 The top views are views showing the positional relationship and structure between the cover member 50 and the airbag cushion 33 according to the first embodiment, and (A) and (B) are views showing the cover member 50 and the airbag cushion 33 reversed. Figure 7 Schematic diagram showing the structure of fibers used for manufacturing the cover member 50 . Figure 81 and 2 are cross-sectional views showing the structures of the airbag cushion 33 and the cover member 50 according to the first embodiment, wherein (A) shows a state before the heating and pressing step, and (B) shows a state after the heating and pressing step. Fig. 9 It is a cross-sectional view showing a state where the airbag device 20 according to the first embodiment is mounted on the seat frame 10 .

[0063] like Figure 8 and Fig. 9 As shown, the airbag cushion 33 includes: a rear chamber portion 33a for accommodating the inflator 30; and a front chamber portion 33b extending forward from the rear chamber portion 33a and arranged outside the seat frame 10 when accommodated. In addition, the rear chamber portion 33a and the front chamber portion 33b of the airbag cushion 33 can be distinguished at the front and rear of the folded portion 50x.

[0064] like Figure 6 As shown, the front chamber portion 33 b of the rolled-up airbag cushion 33 is accommodated in the bag-shaped cover member 50 , and the rear chamber portion 33 a is exposed.

[0065] The cover member 50 compresses and holds a predetermined region 60 corresponding to the front chamber portion 33 b of the airbag cushion 33 by heating and pressurizing the predetermined region 60 .

[0066] The material of the cover member 50 can be a non-woven fabric material containing multiple polymer fibers. The non-woven fabric is provided by felt. The felt can be formed to have a thickness of about 4.25 mm and a density of 300 g / m2. In the present embodiment, the non-woven fabric material (cover member 50) can be a polyester felt manufactured by a known needle process in which polyester fibers are entangled and fixed to each other through needle processing. The polyester fibers can be provided by polyethylene terephthalate (PET), and the felt can be made of 100% PET. In addition, the felt used in the present embodiment can actually contain two fibers with different structures.

[0067] Figure 7 Schematic diagram showing the structure of fibers used for manufacturing the cover member 50 . Figure 7 The fibers 70a on the upper side are all monocomponent fibers formed of PET. Specifically, it is assumed that the monocomponent fibers 70a are all formed of PET homopolymer. On the contrary, Figure 7The fiber 70b on the lower side is a bicomponent composite fiber having a single core 74 and a coating 75 surrounding it. The core 74 and the coating 75 of the bicomponent composite fiber 70b are configured to have different characteristics, especially different melting points, and the coating 75 has a significantly lower melting point than the core 74, for example, in the range of 120 to 150°C. The bicomponent composite fiber 70b can also be formed entirely of PET, but the core 74 can be formed of a PET homopolymer and the coating 75 can be formed of a PET copolymer (co PET). In this way, by combining PET and co PET, the melting point of the coating 75 is lower than the melting point of the core 74, but the fiber 70b can be formed of PET as a whole. Of course, since the core 74 of the bicomponent composite fiber 70b and the monocomponent fiber 70a are both formed of PET homopolymers, they have the same melting point as each other, and the monocomponent fiber 70a has a higher melting point than the coating 75 of the bicomponent composite fiber 70b.

[0068] The bicomponent composite fibers 70b are evenly distributed on the entire monocomponent fibers 70a in the felt material. The bicomponent composite fibers 70b account for 30% to 60% of the total number of fibers in the felt material, and the rest are preferably monocomponent fibers 70a.

[0069] Although repetitive, Figure 6 and Figure 8 As shown, the front chamber portion 33b of the airbag cushion 33 is stored in a rolled or folded state. In addition, the airbag cushion 33 when stored has a bent portion 50x bent at the front edge portion of the seat frame 10 between the front chamber portion 33b and the rear chamber portion 33a.

[0070] In the cover member 50, at least the portion corresponding to the bent portion 50x of the airbag cushion 33 is not heated or pressurized. Fig. 9 As shown, the flexibility of the bent portion 50 x can be ensured, the airbag cushion 33 can be bent relatively easily, and the airbag cushion 33 can be stored in a state of being in close contact with the seat frame 10 .

[0071] The cover member 50 can be divided into at least a front cover region 50a that at least surrounds the front chamber portion 33b of the airbag cushion 33, and a rear cover region 50b that extends rearward of the front cover region 50a and covers at least a portion of the rear chamber portion 33a of the airbag cushion 33. The rear cover region 50b has a first rear edge portion 51b located inside the rear end of the cover member 50 and a second rear edge portion 51a located outside.

[0072] A joint 54 connected to the stud 32 penetrating to the outside of the seat frame 10 is provided at the front end portion of the front cover region 50a of the cover member 50. The joint 54 is heated and pressurized together with the front cover region 50a.

[0073] Both the first rear edge portion 51 b and the second rear edge portion 51 a of the cover member 50 are connected to the rear chamber portion 33 a of the airbag cushion 33 by breakable sewing 52 .

[0074] In this case, when the airbag cushion 33 starts to expand and deploy, the sewn portion 52 is broken, and the cover member 50 releases the holding of the compressed airbag cushion 33 .

[0075] (Manufacturing and assembly process)

[0076] The airbag device 20 according to the present embodiment is manufactured through the following steps and assembled to a seat.

[0077] (Process 1)

[0078] The inflator 30 is housed in a rear chamber portion 33 a of the airbag cushion 33 .

[0079] (Process 2)

[0080] The front chamber portion 33b of the airbag cushion 33 is placed in a rolled or folded state.

[0081] (Process 3)

[0082] The cover member 50 is arranged to cover a portion of the front chamber portion 33b and the rear chamber portion 33a, thereby forming the first intermediate package 20a ( Figure 6 , Figure 8 (A)).

[0083] (Process 4)

[0084] By heating and pressurizing a portion 60 of the cover member 50, the front chamber portion 33b of the airbag cushion 33 is further compressed to form the second intermediate package 20b ( Figure 8 (B)), for example, the first intermediate package 20a is placed in a predetermined mold and pressurized while being heated. The heating step is performed at a temperature higher than the melting point of the coating 75 of the bicomponent composite fiber 70b but lower than the melting points of the core 74 of the bicomponent composite fiber 70b and the single component fiber 70a.

[0085] In addition, although the heating process and the pressurizing process are performed simultaneously, they do not need to be performed completely simultaneously from the beginning to the end. For example, heat can be applied before applying pressure to the first intermediate package 20a. It is important that there is at least a time for applying heat and pressure to the intermediate package at the same time.

[0086] In the pressurizing step, a pressure of 5 to 200 kN is applied to the first intermediate package 20a, and the temperature is maintained at a temperature higher than the melting point of the cover 75 of the bicomponent composite fiber 70b. The overlapping time of the heating step and the pressurizing step depends on the properties of the cover member 50 material, but can be less than 2 minutes.

[0087] When the airbag cushion 33 is formed of plastic cloth, the cloth forming the airbag cushion 33 is compressed and plastically deformed by applying pressure and heat to the first intermediate package 20a. Also, the rolled front chamber portion 33b in the second intermediate package 20b becomes flat.

[0088] In the case where the airbag cushion 33 is not formed of a plastically deformable material, by simultaneously applying pressure and heat to the first intermediate package 20a, the felt material of the cover member 50 is thinned (for example, 0.55 mm), so that it can be plastically deformed. More specifically, when heated at a temperature higher than the melting point of the coating 75 of the two-component composite fiber, the coating 75 dissolves. Therefore, the coating 75 is fused to each other at all positions where the fibers in the cover member 50 are distributed. However, since the cover member 50 is heated at a temperature lower than the melting point of the core 74 of the two-component composite fiber 70b and the single-component fiber 70a of the overall structure, the core 74 and the single-component fiber 70a still maintain a solid phase and do not fuse to each other. As a result, only the material of the coating 75 is fused.

[0089] By fusing only the coating 75 of the bicomponent composite fiber distributed over the entire cover member 50, the second intermediate package 20b maintains a three-dimensional shape even after being removed from the press after the process of heating and pressurizing the package is completed. In this way, the cover member 50 can reliably hold the rolled airbag cushion 33 (33b) in a compressed state generated in the pressurizing process. In addition, since the core 74 of the bicomponent composite fiber 70b and the monocomponent fiber 70a are not fused as a whole, the cover member 50 retains a little softness and adaptability.

[0090] (Process 5)

[0091] The inflator 30 is fixed inside the seat frame 10 .

[0092] (Process 6)

[0093] The front chamber portion 33b and the rear chamber portion 33a of the airbag cushion 33 are bent by 50x, and the front chamber portion 33b is folded back toward the outside of the seat frame 10 ( Fig. 9 ).

[0094] (Process 7)

[0095] like Fig. 9 As shown, the joint 54 of the cover member 50 is coupled to the stud 32 .

[0096] As described above, in the present invention, the cover member 50 that holds the airbag cushion 33 is heated and pressurized at least in the area corresponding to the front chamber portion 33b of the airbag cushion 33, thereby compressing and holding the portion of the airbag cushion 33. That is, the portion (33b) that occupies the main part of the airbag cushion 33 and is arranged outside the seat frame 10 is held in a compressed state by the cover member 50. At this time, the heated and pressurized cover member 50 melts and shrinks, so that the hardness of this portion of the cover member 50 becomes higher than that of other portions, and the shape retention performance is improved. On the other hand, since the rear chamber portion 33a that accommodates the inflator 30 is not compressed via the cover member 50, it is maintained in a relatively soft state and becomes a state that is easy to bend.

[0097] (Second embodiment)

[0098] Fig.10 This is a cross-sectional view showing the structure of the airbag cushion 33 and the cover member 150 according to the second embodiment of the present invention, and shows a state before the heating and pressurizing step (first intermediate package). Figure 1 It is a cross-sectional view showing a state where the airbag device according to the second embodiment is mounted on a seat frame 10 .

[0099] In this embodiment, the same reference numerals are used for the components that are substantially the same as those in the first embodiment. In addition, the 100-series reference numerals are added to the components that correspond to the first embodiment but are changed. For example, the cover member is "50" in the first embodiment, but "150" in the second embodiment. In addition, repeated descriptions are omitted, and only the differences are described.

[0100] In this embodiment, the first rear edge portion 151b of the cover member 150 is fixed to the stud 32 inside the seat frame 10. In addition, the second rear edge portion 151a of the cover member 150 is connected to the rear chamber portion 33a of the airbag cushion 33 by sewing 152.

[0101] A fragile slit 155 is formed in the second rear edge 151a of the cover member 150 near the sewing 152. When the airbag cushion 33 begins to deploy, the cover member 150 is accurately broken in the slit 155, and interference between the airbag cushion 33 and the cover member 150 can be minimized.

[0102] (Third embodiment)

[0103] Fig.12 This is a cross-sectional view showing the structure of an airbag cushion 33 and a cover member 250 according to a third embodiment of the present invention, showing a state before a heating and pressurizing step (a first intermediate package). Fig.13 1 is a cross-sectional view showing an airbag device according to a third embodiment mounted on a seat frame 10 .

[0104] In this embodiment, the same reference numerals are used for the components that are substantially the same as those in the first embodiment. In addition, the 200-series reference numerals are added to the components that correspond to the first embodiment but are changed. For example, the cover member is "50" in the first embodiment, but "250" in the third embodiment. In addition, repeated descriptions are omitted, and only the differences are described.

[0105] This embodiment is the same as the above-mentioned second embodiment. The second rear edge portion 251b of the cover member 250 is connected to the stud 32 of the inflator 30 on the inner side of the seat frame 10. In addition, the first rear edge portion 251b and the second rear edge portion 251a of the cover member 250 are connected to the rear chamber portion 33a of the airbag cushion 33 by sewing 252.

[0106] (Fourth embodiment)

[0107] Fig.14 This is a cross-sectional view showing the structure of an airbag cushion 33 and a cover member 250 according to a fourth embodiment of the present invention, showing a state before a heating and pressurizing step (a first intermediate package). Figure 5 It is a cross-sectional view showing a state where the airbag device according to the fourth embodiment is mounted on a seat frame 10 .

[0108] In this embodiment, the same reference numerals are used for the components that are substantially the same as those in the first embodiment. In addition, the 300 series of numerals are added to the components that correspond to the first embodiment but are changed. For example, the cover member is "50" in the first embodiment, but "350" in the third embodiment. In addition, repeated descriptions are omitted, and only the differences are described.

[0109] In this embodiment, the first rear edge portion 351b and the second rear edge portion 351a are fixed to the stud 32 so that the rear cover region 350b of the cover member 350 surrounds the rear chamber portion 33a of the airbag cushion 33. A slit 355 is formed in a portion of the rear cover region 350b of the cover member 350.

[0110] In this embodiment, the cover member 350 not only surrounds the front chamber portion 33b of the airbag cushion 33, but also surrounds the entirety including the rear chamber portion 33a. Therefore, the second intermediate package (20b) including the airbag cushion 33, the cover member 350, and the inflator 30 can be accurately installed on the seat frame 10 in an ideal posture.

[0111] Although the present invention has been described with reference to the embodiments, the present invention is not limited to these embodiments and can be appropriately modified within the scope of the technical concept of the present invention. For example, in the above embodiments, the near-side side airbag is described with emphasis, but the present invention can also be applied to far-side side airbags (farther from the door of the vehicle seat), single-seat vehicles (regardless of whether there are doors or not, including vehicles with only one seat in a row) in ultra-small vehicles such as compact light vehicles, etc.

[0112] In addition, in the above description, the present invention specifically describes the embodiment using a felt type nonwoven fabric material, but a woven fabric may also be used as long as it has ductility.

Claims

1. An airbag device housed in a vehicle seat, characterized in that: include: an airbag cushion, which inflates and deploys to restrain an occupant; an inflator disposed inside a vehicle seat frame and supplying inflation gas to the airbag cushion; a cover member formed of a ductile material that melts and shrinks by heating and pressurizing and is used to hold the airbag cushion, The airbag cushion includes a rear chamber portion for accommodating the inflator and a front chamber portion extending forward from the rear chamber portion and disposed outside the seat frame when the inflator is accommodated. The cover member is configured to compress and hold the portion of the airbag cushion by heating and pressurizing at least a region corresponding to the front chamber portion of the airbag cushion. The rear chamber portion housing the inflator is not covered by the cover member, When the airbag cushion is stored, the airbag cushion has a curved portion between the front chamber portion and the rear chamber portion that is curved at the front edge portion of the seat frame. A portion of the cover member corresponding to the bent portion of the airbag cushion is not heated or pressurized.

2. The airbag device according to claim 1, characterized in that: The front chamber portion of the airbag cushion is stored in a rolled or folded state.

3. The airbag device according to claim 1 or 2, characterized in that: The cover member is formed of a ductile cloth material containing a plurality of polymer fibers, and is configured to be able to maintain a predetermined shape by welding at least a portion of the fibers to each other.

4. The airbag device according to claim 1 or 2, characterized in that: The cover member includes: a front cover region that at least surrounds the front chamber portion of the airbag cushion; and a rear cover region that extends rearward of the front cover region and covers at least a portion of the rear chamber portion of the airbag cushion. The rear cover region includes a first rear edge portion located inside the rear end of the cover member and a second rear edge portion located outside.

5. The airbag device according to claim 4, characterized in that: The inflator is a structure that is fixed to the seat frame by studs, A joint connected to the stud penetrating the outside of the seat frame is provided at an end portion of the front cover region of the cover member.

6. The airbag device according to claim 5, characterized in that: Heat and pressure are applied to the joint.

7. The airbag device according to claim 6, characterized in that: The second rear edge portion of the cover member is connected to the rear chamber portion of the airbag cushion by sewing.

8. The airbag device according to claim 6 or 7, characterized in that: The first rear edge portion of the cover member is fixed to the inner side of the seat frame by the stud.

9. The airbag device according to claim 8, characterized in that: Both the first rear edge portion and the second rear edge portion of the cover member are connected to the rear chamber portion of the airbag cushion by sewing in a breakable manner.

10. The airbag device according to claim 6 or 7, characterized in that: A fragile slit is formed in the second rear edge portion of the cover member near the sewing.

11. A method for manufacturing an airbag device, wherein the airbag device is accommodated in a vehicle seat, the method for manufacturing the airbag device comprising: include: The step of accommodating an inflator in a rear chamber portion of the airbag cushion; The process of compressing the front chamber portion of the airbag cushion into a rolled or folded state; A step of arranging a cover member formed of a ductile material that melts and shrinks by heating and pressurizing so as to cover the front cavity portion to form a first intermediate package; a step of heating and pressurizing a portion of the cover member to further compress the front chamber portion of the airbag cushion to form a second intermediate package; The step of fixing the inflator to the inner side of the seat frame; The step of bending the front chamber portion and the rear chamber portion of the airbag cushion to form a curved portion, and disposing the front chamber portion outside the seat frame; a step of connecting the end of the cover member to the seat frame, A portion of the cover member corresponding to the bent portion of the airbag cushion is not heated or pressurized.

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