JP2023031194A - Air bag cover - Google Patents

Abstract

To provide an air bag cover capable of improving opening performance of a door part.SOLUTION: An air bag cover 20 includes: an air bag cover body 31 formed of a synthetic resin-made base material 32 arranged in an area including a door part 24 opened by pushed with an expanded air bag 11, and a synthetic resin-made retainer 50 which is bonded to the side of a rear face 32b side of the base material and is softer than the base material; and a skin layer 62 on the surface side of the air bag cover body. The door part includes a door constitution part 35 of the base material, and a door support part 58 of the retainer holding the door constitution part. The retainer includes a door support part, a peripheral edge part 51 in the periphery of the door support part, and a hinge part 60 which is bendable between the peripheral edge part and the door support part. The base material has a space part 47 provided in an arrangement part of the hinge part of the retainer, and it is used as a non-arrangement part of the base material. The region of the hinge part is composed of two layers of the hinge part of the retainer, and the skin layer bonded to the hinge part.SELECTED DRAWING: Figure 2

Description

INDUSTRIAL APPLICABILITY The present invention is used in an airbag device having an airbag that inflates to protect an occupant or the like, covers the folded airbag, and forms a projecting opening when the airbag is inflated to The present invention relates to an airbag cover configured to protrude the bag.

Conventionally, an airbag cover arranged on an instrument panel of a vehicle has a structure having a door portion that opens when pushed by the airbag so as to form an opening for projecting the airbag when the airbag is inflated. , a base material made of synthetic resin such as polypropylene that is arranged in the area including the door part, and a synthetic resin material such as olefinic thermoplastic elastomer that is arranged in the area where the door part is arranged and is softer than the base material and a retainer, and the base material and the retainer are integrally molded by two-color molding using a molding material (see, for example, Patent Document 1). In this airbag cover, the door portion includes the door-constituting portion of the base material and the door supporting portion provided on the retainer to hold the door-constituting portion. The retainer includes a door support portion, a peripheral portion arranged around the door support portion, and a hinge portion arranged between the peripheral portion and the door support portion and bent when the door portion is opened. was configured In this airbag cover, unlike the conventional configuration in which the substrate and the retainer are separately formed and vibration-welded (see Patent Document 2), a two-color molded product is used, and the hinge portion of the retainer is made bulky. Instead of a curved structure, a substantially flat plate-like structure is used to ensure flexibility. This hinge portion was connected to the back side of the base material as a thin, substantially flat plate.

Japanese Patent Application Laid-Open No. 2009-248610 (see FIGS. 1 and 2) Japanese Patent Application Laid-Open No. 2009-248610 (see FIGS. 3 and 4)

However, in the airbag cover described in Patent Literature 1, although the hinge portion of the retainer is thin to ensure flexibility, it is joined to the base material corresponding to the hinge portion by two-color molding. Since the base material is also bent when the door is opened, there is room for improvement in further improving the opening performance of the door.

SUMMARY OF THE INVENTION An object of the present invention is to provide an airbag cover capable of improving the opening performance of a door portion.

In the airbag cover according to the present invention, when the airbag is inflated, the door portion is opened by being pushed by the airbag so as to form an opening for projecting the airbag, and
a synthetic resin base material arranged in an area including the door portion;
a retainer made of a synthetic resin that is softer than the base material and is coupled to the rear surface side of the base material in the arrangement area of the door portion,
wherein the door portion includes a door-constituting portion of the base material and a door supporting portion provided on the retainer and holding the door-constituting portion;
The retainer includes the door support portion, a peripheral portion provided around the door support portion, and the retainer provided between the peripheral portion and the door support portion so as to be bent when the door portion is opened. An airbag cover comprising a substantially flat hinge portion,
an airbag cover body comprising the base material and the retainer;
a skin layer adhered to the surface side of the airbag cover body and having flexibility that can be broken when the door is opened;
configured with
A space is provided in a portion where the base material is provided with the hinge portion of the retainer as a non-arranged portion of the base material,
The area of the hinge portion is composed of two layers, the hinge portion of the retainer and the skin layer adhered to the hinge portion.

In the airbag cover according to the present invention, the hinge portion when the door portion is opened is a non-base member portion having a space, and is not provided with a base member, and has a flexible skin. It is composed of two layers: a layer and a hinge portion of the retainer made of a synthetic resin softer than the base material. Therefore, since the base material itself is not bent when the door is opened, the hinge portion is smoothly bent to open the door. In addition, since the surface of the airbag cover body including the base material and the retainer is provided with a skin layer including the hinge part, the base material including the space is not exposed on the surface side, so that the air The design of the bag cover is improved.

Therefore, in the airbag cover according to the present invention, the opening performance of the door portion can be improved, and the design can be improved.

In the airbag cover according to the present invention, the door portion has the skin layer, the door-constituting portion of the base material, and the door support portion of the retainer arranged from the outer surface side. It should preferably consist of layers.

In such a configuration, the door portion is the general area of the airbag cover excluding the door portion arrangement area, i.e., the general area where the retainer is not provided, as well as the back surface of the surface side skin layer. Since the base material is arranged on the side of the door and the skin layer of the door part is supported by the base material on the back side, the tactile sensation of the door part is made equivalent to the tactile sensation of the general part. be able to.

Further, in the airbag cover according to the present invention, a portion to be broken that is pushed by the inflating airbag and broken is provided around the door portion excluding the portion where the hinge portion is provided,
It is desirable that the portion to be broken is composed of two layers, the skin layer and the base material provided with the weakened portion, as a portion where the retainer is not provided.

In such a configuration, since the portion to be broken that is to be broken when the door is opened is configured without a retainer portion, the portion to be broken that is pushed open by the inflating airbag can be broken. Composed of only two layers of a skin layer and an easily broken base material provided with a fragile portion, the portion to be broken is smoothly broken when the door portion is opened, and the opening performance of the door portion is improved. can be stabilized.

Further, in the airbag cover according to the present invention, the retainer is configured by arranging a connecting wall portion connected to a mounting base of an airbag device that holds the folded airbag on the peripheral edge portion. It is desirable that

In such a configuration, the installation area of the door portion of the airbag cover is connected to the mounting base for holding the folded airbag in the airbag device via the connecting wall portion extending from the peripheral edge portion of the retainer. When the airbag is inflated, the peripheral edge of the retainer is connected to the mounting base of the airbag device and does not move away from the mounting base side, so that the peripheral edge of the retainer is connected via the hinge. The door part of the structure can receive the pressing force of the inflating airbag accurately and can be opened quickly.

Further, in the airbag cover according to the present invention, the outer area of the hinge portion in the arrangement area of the door portion is formed of three layers of the skin layer, the base material, and the retainer. It is desirable to have

In such a configuration, even if the hinge portion of the retainer is not coupled to the base material of the airbag cover body, the peripheral edge portion of the retainer is coupled. Even if a strong tensile force is applied to the hinge portion of the retainer, the portion of the peripheral portion of the retainer near the hinge portion is bonded to the base material and prevented from peeling off from the base material. The hinge portion (the hinge portion of the retainer) can be smoothly opened without affecting the surface layer or the like in the general area of the bag cover where the retainer is not provided.

Further, in the airbag cover according to the present invention, it is preferable that the airbag cover main body is integrally formed by two-color molding using a molding material for the base material and the retainer.

In such a configuration, compared to the case where the base material and the retainer are separately formed and bonded by vibration welding or the like to form the airbag cover main body, or the airbag cover main body is formed by insert molding, Since it is possible to efficiently form the airbag cover body by reducing mold costs and man-hours, it is possible to contribute to a reduction in man-hours and costs for manufacturing the airbag cover.

1 is a schematic perspective view of an airbag device using an airbag cover of one embodiment according to the present invention; FIG. 1 is a schematic longitudinal sectional view along the front-rear direction of an airbag device according to an embodiment; FIG. FIG. 2 is a schematic partial enlarged vertical cross-sectional view along the front-rear direction of the airbag device of the embodiment; 1 is a schematic vertical cross-sectional view of an airbag device according to an embodiment along the left-right direction; FIG. FIG. 4 is a plan view of the airbag cover of the embodiment near an area where a door portion is provided; It is a bottom view near the arrangement|positioning area of the door part in the airbag cover of embodiment. It is a bottom view which shows the site|part of the part to be broken of the base material of embodiment. FIG. 8 is a schematic enlarged bottom view showing the vicinity of the fracture starting point of the portion to be fractured in the substrate of the embodiment, corresponding to the VIII portion of FIG. 7, and also showing a schematic cross-sectional view of the vicinity of that portion. FIG. 4 is a schematic enlarged bottom view showing the vicinity of the fracture starting point of the portion to be fractured in the base material of the embodiment. FIG. 8 is a schematic enlarged bottom view showing the vicinity of the side edge of the door portion in the base material of the embodiment, corresponding to the X portion in FIG. It is a figure explaining the manufacturing process of the airbag cover of embodiment, and shows the process of manufacturing a base material. It is a figure explaining the manufacturing process of the airbag car of embodiment, and shows the process of manufacturing a retainer. FIG. 12 shows a process of manufacturing a retainer after the process shown in FIG. 12, and further shows a process of adhering skin layers. FIG. 4 is a schematic enlarged vertical cross-sectional view for explaining the beginning of opening of the door portion in the airbag cover of the embodiment; FIG. 10 is a schematic vertical cross-sectional view along the left-right direction of an airbag device using an airbag cover of a modified example; FIG. 16 is a plan view of the substrate in the vicinity of the arrangement area of the door portion of the airbag cover shown in FIG. 15;

An embodiment of the present invention will be described below with reference to the drawings. As shown in FIGS. It is used in an airbag device 10 for a passenger seat. The instrument panel 2 is disposed below the front windshield 1a on the front side of the front seats of the vehicle 1, and includes a driver seat side portion 2a on the front side of the driver's seat, a passenger seat side portion 2b on the front passenger seat, and a passenger seat side portion 2b on the front passenger seat. The front passenger side portion 2b of the center console is formed so as to smoothly protrude the airbag 11 (see FIG. 2) when the airbag 11 (see FIG. 2) is inflated. It is configured as a portion of the airbag cover 20 that forms a projection opening 68 that is a rectangular opening.

As shown in FIGS. 2 and 4, the airbag device 10 is supplied with an airbag 11 that is inflated to protect the occupant in the front passenger seat by inflating the gas G for inflation, and supplies the gas G for inflation to the airbag 11. an airbag cover 20 for covering the folded and stored airbag 11; and a mounting base 15 for storing and holding the folded airbag 11 and the inflator 14. . The mounting base 15 is connected to the body side of the vehicle 1 by a bracket (not shown). The instrument panel 2 provided with the airbag cover 20 is held on the body side of the vehicle 1 in the vicinity of the outer peripheral edge and the like, and is attached to the mounting base 15 at the portion of the airbag cover 20 using the connecting wall portion 53 described later. concatenated.

The airbag 11 is formed of a woven fabric such as polyester, and has a substantially truncated quadrangular pyramid shape that is tapered toward the front side with a receiving surface for receiving a passenger in the passenger seat at the rear end, An inflow opening 11a for inflowing the inflation gas G is provided on the lower surface on the front end side. The inflow opening 11a has a circular shape, and the peripheral edge of the inflow opening 11a is held by a substantially square annular retainer 12 disposed in the airbag 11 and attached to the bottom wall portion 16 of the mounting base 15. It is The retainer 12 has downwardly extending bolts 12a protruding from four corners of a substantially rectangular ring shape. Each bolt 12a penetrates the periphery of the inflow opening 11a of the airbag 11, the bottom wall portion 16 of the mounting base 15, which will be described later, and the flange portion 14c, which will be described later, of the inflator 14, and is fastened with a nut 13. , the airbag 11 and the inflator 14 are attached and fixed to the bottom wall portion 16 of the attachment base 15 .

The inflator 14 includes a main body portion 14a having a substantially cylindrical shape and having a gas discharge port 14b for discharging the inflation gas G at its upper portion, and a flange portion protruding from the outer peripheral surface of the main body portion 14a and through which the bolts 12a of the retainer 12 pass. 14c.

The mounting base 15 is made of sheet metal and includes a substantially rectangular plate-shaped bottom wall portion 16 and a substantially rectangular cylindrical side wall portion 17 extending upward from the outer peripheral edge of the bottom wall portion 16 . The bottom wall portion 16 has an insertion hole 16a into which the main body portion 14a of the inflator 14 is inserted from below. The periphery of the inflow opening 11a of the airbag 11 and the flange portion 14c of the inflator 14 are attached and fixed to the bottom wall portion 16 of the attachment base 15 by the bolts 12a and nuts 13 of the retainer 12. . The side wall portion 17 is formed with an engaging hook 17 a that is engaged with an engaging hole 54 provided in the connecting wall portion 53 of the retainer 50 . The locking hooks 17a are arranged in the front and rear portions of the side wall portion 17, and are arranged side by side along the left-right direction.

As shown in FIGS. 1 to 6, the airbag cover 20 has a door portion 24 (F, B). The door portions 24 (F, B) are configured to open so as to form a projection opening 68. The projection opening 68 is a substantially rectangular shape similar to the bottom wall portion 16 of the mounting base 15 of the airbag device 10. It has a shape that opens to The door portions 24F and 24B of the embodiment are configured to open on both front and rear sides like a double door, and when opened, the regions obtained by dividing the projection opening 68 in front and back are opened respectively.

Further, the airbag cover 20 includes a door installation area 22 in which the door portions 24 (F, B) are arranged, and a general portion 21 surrounding the door installation area 22 . The door arrangement area 22 includes the door portions 24F and 24B themselves, the hinge portions 25 thereof, the breakable portions 27 for breaking the peripheral edges of the door portions 24F and 24B for opening the door portions 24F and 24B, and further, A region of a peripheral portion 51 of the retainer 50, which will be described later. The portion to be broken 27 is disposed on the periphery of the door portions 24F and 25B that open to both the front and rear sides, and when viewed from above, a horizontal line portion 28 extending in the left-right direction at the boundary portion between the front and rear door portions 24F and 25B. , and vertical line portions 29 (L, R) extending in the front-rear direction on both the left and right sides are arranged in a substantially H-shape.

Furthermore, the airbag cover 20 has a structure including an airbag cover main body 31 and a skin layer 62 adhered to the surface side of the airbag cover main body 31 .

The airbag cover main body 31 includes a base material 32 made of synthetic resin such as polypropylene disposed in an area including the door portions 24 (F, B), and an area 22 in which the door portions 24 (F, B) are disposed. and a retainer 50 made of a synthetic resin such as an olefinic thermoplastic elastomer softer than the base material 32 so as to be connected to the back surface 32b side of the base material 32 in the base material 32 . In the case of the embodiment, the airbag cover main body 31 is configured as a two-color molded product in which the base material 32 and the retainer 50 are integrally molded by two-color molding of the molding material.

The base material 32 and the skin layer 62 of the airbag cover main body 31 extend not only to the passenger seat side portion 2b, which is the area of the airbag cover 20 of the instrument panel 2, but also to the driver seat side portion 2a and the central portion 2c. is set. That is, the general portion 21 of the airbag cover 20 is composed of the base material 32 of the airbag cover main body 31 and the skin layer 62, and also on the side of the driver's seat side portion 2a and the central portion 2c side of the instrument panel 2, It is arranged so as to extend.

The door portions 24F and 24B of the airbag cover 20 are provided on the door constituent portions 35F and 35B of the base material 32 and the retainer 50, and are arranged so as to hold the respective door constituent portions 35F and 35B from the back side. Door support portions 58F and 58B coupled to the door structure portions 35F and 35B, and a door skin portion 66 of the skin layer 62 is adhered to the surface side of each of the door structure portions 35F and 35B. are arranged.

The skin layer 62 includes a fabric 63 as a skin disposed on the surface 62a side, and a sheet-like cushion layer 64 to which the fabric 63 is adhered. The fabric 63 is a woven fabric woven using yarns such as polyester as warp yarns and weft yarns. The cushion layer 64 is made of a cushioning material such as polypropylene. The skin layer 62 is composed of a door skin portion 66 arranged on the surface side of each of the door portions 24F and 24B and a general portion 65 surrounding it. A boundary portion between the peripheral edge of the door skin portion 66 and the general portion 65 is arranged at a portion to be broken 27, and is broken when the door portion 24 (F, B) is opened.

The retainer 50 includes the above-described door support portions 58 (F, B), a peripheral edge portion 51 arranged around the door support portions 58 (F, B), and the peripheral edge portion 51 and the door support portion 58 (F, B). B) so as to connect the peripheral portion 51 and the base portion 58b of each door support portion 58 (F, B), and is flexible when the door portion 24 (F, B) opens. and a substantially flat hinge portion 60 (F, B) having a thin wall. The retainer 50 has a gap 56 corresponding to the breaking portion 27 between the peripheral edge of the door support portion 58F and the hinge portion 60F, the peripheral edge of the door support portion 58B and the hinge portion 60B, and the inner peripheral side of the peripheral edge portion 51. is provided. That is, when viewed from above, the gap 56 includes a horizontal rod portion 56a corresponding to the horizontal line portion 28 of the portion to be broken 27 and a vertical rod portion corresponding to the left and right vertical line portions 29 (L, R) of the portion to be broken 27. 56b (L, R) and has a substantially H shape (see FIG. 6).

In the case of the embodiment, the base member 32 is provided with a space portion 47 (F, B) at the portion where the hinge portion 60 (F, B) of the retainer 50 is arranged, so that the hinge portion 60 (F, B) is provided with a space portion 47 (F, B). A portion is defined as a non-arrangement portion where the base material 32 is not arranged. Therefore, in the airbag cover 20, the hinge portion 25 of the door portion 24 (F, B) becomes the region of the hinge portion 60 (F, B) of the retainer 50, and the hinge portion 60 (F, B) of the retainer 50 and a skin layer 62 adhered to the hinge portion 60 (F, B).

In addition, the peripheral edge portion 51 of the retainer 50 is provided with a flange portion 52 that extends outward from the upper end of a rectangular cylindrical connecting wall portion 53 that extends downward and has a substantially square annular shape that is disposed around the peripheral edge of the projection opening 68 . It is configured. The flange portion 52 includes a front flange portion 52a, a rear flange portion 52b, a left flange portion 52c, and a right flange portion 52d, which are arranged on the front, rear, left, and right of the connecting wall portion 53. As shown in FIG. In addition, the peripheral edge portion 51 is provided with inner projecting portions 52ca and 52da extending inwardly of left and right wall portions 53c and 53d of the connecting wall portion 53, which will be described later.

A locking hole 54 into which the locking hook 17a of the mounting base 15 of the airbag device 10 is inserted is formed in the front wall portion 53a and the rear wall portion 53b of the connecting wall portion 53 of the retainer 50 (see FIG. 1). 2).

The base member 32 includes a door installation area 34 arranged in the door installation area 22 of the airbag cover 20, a general portion 33 arranged in the general portion 21 of the airbag cover 20 around the door installation area 34, is configured with The door arrangement area 34 includes door structure portions 35 (F, B), space portions 47 (F, B) formed as rectangular openings provided on the base portion 35b side of each door structure portion 35, and each door. It is composed of fragile portions 36 that are arranged at the tip edge 35a and the side edge 35d of the component portions 35F and 35B and constitute the portion to be broken 27, and a peripheral edge joint portion 48 that is joined to the peripheral edge portion 51 of the retainer 50. (see FIG. 7).

The peripheral edge coupling portion 48 includes a front side portion 48a coupled to the front side collar portion 52a of the collar portion 52 of the peripheral portion 51, a rear side portion 48b coupled to the rear side collar portion 52b, and a left side portion coupled to the left side collar portion 52c. 48c, and a right side portion 48d coupled to the right flange portion 52d. The left and right left and right portions 48c and 48d extend to the vertical rod portions 56bL and 56bR of the gap 56 of the retainer 50 and extend to the vicinity of the left and right side edges 35d of the door structure portions 35F and 35R. Portions 48ca and 48da are provided (see FIGS. 2, 3, 6 and 7). The inner protruding portions 48ca and 48da are configured such that the inner protruding portions 52ca and 52da of the retainer 50 are coupled to the lower side of a portion of the weakened portion 36 side.

The fragile portion 36 that constitutes the portion to be broken 27 has a plurality of strip-shaped breaking openings 37 along the horizontal line portion 28 and the vertical line portion 29 (L, R) of the approximately H-shaped portion to be broken 27. , a plurality of breakage connection portions 41 (A, B), 45 arranged to block the breakage openings 37 and broken when the airbag 11 is inflated ( 5 and 7).

At the horizontal line portion 28 of the portion to be broken 27, the breaking connection portion 41 (A, B) is arranged so as to close the breaking opening 37 (see FIGS. 8 and 9), and the vertical line portion 29 ( L, R), a breaking connecting portion 45 is arranged so as to close the breaking opening 37 (see FIG. 10).

In the case of the embodiment, the vicinity of the center portion 28a in the left-right direction of the horizontal line portion 28 is the starting point portion of the breakage when the door portion 24 (F, B) is opened.

The breaking connecting portions 41 (A, B) arranged on the horizontal line portion 28 are arranged such that the width dimension between the adjacent breaking openings 37, 37 in plan view is the leading edge of the front side door constituting portion 35F. The side of the base portion 41a, which is the side of 35a, is smaller than the side of the distal end portion 41b (see FIGS. 8 and 9). That is, in the plan view of the breakage connecting portions 41 (A, B), the width dimensions W11 and W21 of the base portion 41a on the front side are wider than the width dimensions W12 and W22 of the tip portion 41b on the rear side. and

In the case of the embodiment, 14 breaking connecting portions 41 (A, B) are arranged in the horizontal line portion 28, and four breaking connecting portions 41A are arranged in the area near the central portion 28a. , five rupture connecting portions 41B are arranged on the left and right sides, respectively, deviated from the vicinity of the central portion 28a.

The breaking connecting portion 41A in the vicinity of the central portion 28a has side edges 42, 43 in the width direction (left-right direction) of the neighboring breaking openings 37, 37 and opposite edges 38, 39 of the breaking opening 37 facing each other in the front-rear direction. , the intersection angle θA on the side of the tip portion 41b is an acute angle (approximately 60° in the case of the embodiment).

Moreover, as shown in FIG. At the intersection angle between the side edges 42 and 43 in the width direction (left and right direction) of the side and the opposing edges 38 and 39 facing each other in the front and back direction of the breaking opening 37, the tip portion 41b side that is the rear side (door portion 24B side) Although the crossing angle θB is acute, it is larger than that of the breaking connection portion 41A (approximately 75° in the case of the embodiment).

The thickness dimension Bt2 of the base material 32 is about 3 mm, the opening width dimension H0 of the breaking opening 37 is about 1 mm, and the width dimension W11 of the root portion 41a of the breaking connecting portion 41A is about 4.2 mm. The width W12 of the distal end portion 41b is approximately 3 mm, the width W21 of the root portion 41a of the breaking connecting portion 41B is approximately 4.54 mm, and the width W22 of the distal end portion 41b is approximately 4 mm.

In addition, although the breaking connecting portions 45 arranged in the vertical line portions 29 (L, R) are arranged so as to block the adjacent breaking openings 37, they are shaped like a drum in a plan view, and are used for breaking. The side edges 45d and 45e on the side of the opening 37 are semicircular, and the base portion 45a on the side of the door components 35F and 35B and the tip portion 45b on the side of the left side 48c and the right side 48d of the peripheral edge connecting portion 48 are symmetrical. It is formed as a shape (see FIG. 10). Two hourglass-shaped breaking connecting portions 45 are provided on each side of the left and right side edges 35d of the door-constituting portions 35F and 35B. The vicinity of the narrow middle portion 45c between the root portion 45a on the (F, B) side and the tip portion 45b on the side away from the door portion 24 (F, B) is broken. The width dimension W3 of the intermediate portion 45c is approximately 3 mm.

The vertical line portions 29 (L, R) are arranged on the side edge 35d side of the front door structure portion 35F on the front side and on the side edge 35d side of the door structure portion 35B on the rear side on the rear side. In the center portion 29a in the front-rear direction, a Y-shaped breaking opening 37 extends from the breaking connecting portion 41 on the side of the horizontal line portion 28 to both front and rear sides, with the breaking connecting portion 45 interposed therebetween. It is formed so as to extend the breaking opening 37 forward and backward (see FIGS. 5 and 7).

The front and rear door-constituting portions 35 (F, B) of the base material 32 have a tapered portion 35c in which the base portion 35b on the space portion 47 (F, B) side becomes thinner toward the space portion 47 (F, B) side. As (see FIGS. 2 and 3), the tip edge 35a side is formed as a flat plate having the same thickness across the horizontal line portion 28 of the breaking portion 27 in the fragile portion 36. As shown in FIG. Except for the tapered portion 35c of the base material 32, the thickness dimension Bt2 of the door arrangement area 34 of the door structure portion 35 (F, B) and the peripheral edge joint portion 48 is set equal to the thickness dimension Bt1 of the general portion 33. It is approximately 3 mm.

Further, in the retainer 50, the thickness dimension Rt1 of the flange portion 52 is about 4 mm, the thickness dimension Rt2 of the door support portion 58 (F, B) is about 2 mm, and the thickness dimension of the hinge portion 60 (F, B) is about 2 mm. Rt3 is approximately 1 mm within a range of approximately 0.5 to 1.5 mm (see FIG. 3).

The thickness dimension St0 of the skin layer 62 is approximately 2.6 mm.

When manufacturing the airbag cover 20, first, the airbag cover main body 31 is molded. As shown in FIGS. 11 to 13, the molding die 70 can perform two-color molding using molding materials M1 and M2 for the base material 32 and the retainer 50. A split mold 73 capable of molding the base material 32 , 74 and a split mold 75 capable of molding the retainer 50 using the split mold 73 in common. When the split molds 73 and 74 are closed, a cavity 71 capable of molding the base material 32 is formed from the mold surfaces 73a and 74a. Material 32 may be formed. After that, the mold is opened, and the split mold 74 is replaced with the split mold 75 in a state where the base material 32 is held on the split mold 73 side. A cavity 72 capable of molding the retainer 50 is formed from 73a and 75a, and if a predetermined molding material M2 is injected into the cavity 72 and solidified, the retainer 50 can be formed in a state of being bonded to the base material 32. can. Then, the slide cores 77 and 78 are slid to open the mold, take out the airbag cover main body 31 as a two-color molded product, and bond the skin layer 62 to manufacture the airbag cover 20. can.

The fragile portion 36 and the space 47 (F, B) of the base material 32 forming the breakable portion 27 are integrally formed when the base material 32 is molded by the split molds 73 and 74 .

To assemble the airbag device 10 using the airbag cover 20 manufactured in this way, first, the airbag 11 is folded with the retainer 12 housed in the airbag 11, and then folded with a wrapping material (not shown). The airbag 11 is wrapped and the airbag 11 is housed in the mounting base 15.例文帳に追加At this time, each bolt 12a of the retainer 12 projects downward from the bottom wall portion 16 of the mounting base 15. As shown in FIG. Next, the body portion 14a of the inflator 14 is inserted from below into the insertion hole 16a of the mounting base 15, the bolts 12a of the retainer 12 are passed through the flange portion 14c of the inflator 14, and nuts are attached to the bolts 12a. By fastening 13 , the folded airbag 11 and the inflator 14 can be attached and fixed to the attachment base 15 .

After that, the instrument panel 2 is fixed to the body of the vehicle 1, and the locking hooks 17a of the mounting base 15 are inserted into and locked to the locking holes 54 of the connecting wall portion 53 of the retainer 50 of the airbag cover 20, and the predetermined By connecting a lead wire (not shown) extending from the control device and used for inputting an actuation signal to the inflator 14 and fixing the mounting base 15 to the body side of the vehicle 1 using a predetermined bracket, the airbag can be The device 10 can be mounted on the vehicle 1 .

In the airbag device 10 mounted on the vehicle 1 as described above, when the inflator 14 operates to discharge the inflation gas G, the airbag 11 is inflated by the inflow of the inflation gas G. When the airbag 11 is inflated, the airbag cover 20 ruptures the rupture connection portions 41 (A, B) and 45 in the fragile portion 36 of the base material 32 constituting the portion to be ruptured 27 , thereby opening the door portion 24 . (F, B) bends the hinge portion 60 (F, B) of the retainer 50 at the hinge portion 25, breaks the skin layer 62, and is pushed open to open the projection opening 68. The airbag 11 protrudes from 68 (see two-dot chain line in FIG. 2).

In the airbag cover 20 of the embodiment, the hinge portion 25 when the door portions 24F and 24B are opened does not use the base material 32 as the non-arrangement portion of the base material 32 provided with the space portions 47 (F, B). It is composed of two layers: a flexible skin layer 62 and hinge portions 60 (F, B) of the retainer 50 made of synthetic resin softer than the base material 32 . Therefore, when the door portions 24F and 24B are opened, the base material 32 itself is not bent, so that the hinge portion 25 is smoothly bent and the door portions 24F and 24B are opened. In addition, on the surface of the airbag cover main body 31 including the base material 32 and the retainer 50, a skin layer 62 is provided, including the hinge portion 25, and the base material 32 forms the space 47 (F, B). Since the airbag cover 20 is not exposed to the surface side, the design of the airbag cover 20 is improved.

Therefore, in the airbag cover 20 of the embodiment, the opening performance of the door portions 24 (F, B) can be improved, and the design can be improved.

In the embodiment, the base portion 35b of the door-constituting portion 35 (F, B) of the base material 32 is provided with a tapered portion 35c toward the hinge portion 60 (F, B) side of the retainer 50 to gradually reduce the wall thickness. , the space 47 (F, B), the base member 32, which is harder than the retainer 50, does not hinder the bending performance of the hinges 60 (F, B) of the retainer 50, and the door portion 24 can be smoothly moved. (F, B) can be opened.

In the airbag cover 20 of the embodiment, the door portion 24 (F, B) is composed of, from the outer surface side, the skin layer 62, the door-constituting portion 35 (F, B) of the substrate 32, and the door of the retainer 50. It is composed of three layers in which support portions 58 (F, B) are arranged.

Therefore, in the embodiment, the door portion 24 (F, B) is the area of the general portion 21 excluding the arrangement area 22 of the door portion 24 (F, B) in the airbag cover 20, that is, the retainer 50 is provided. In the same manner as the area of the general portion 21 where there is no surface, the base material 32 is arranged on the back side of the skin layer 62 on the front side, and the skin layer 62 of the door portion 24 (F, B) is on the back side. Therefore, the tactile sensation of the door portions 24 (F, B) can be made equivalent to the tactile sensation of the general portion 21 .

In addition, in the airbag cover 20 of the embodiment, a rupture that is pushed by the inflating airbag 11 and ruptures is provided around the door portion 24 (F, B) except for the portion where the hinge portion 60 (F, B) is arranged. A planned portion 27 is provided, and the planned breaking portion 27 is composed of two layers, that is, a skin layer 62 and a base material 32 provided with a fragile portion 36 as a portion where the retainer 50 is not provided.

Therefore, in the embodiment, since the portion to be broken 27 to be broken when the door portion 24 (F, B) is opened is configured without the portion of the retainer 50, it is pushed by the inflating airbag 11. The breakable portion 27 to be opened is composed of only two layers, that is, the breakable skin layer 62 and the easily breakable base material 32 provided with the fragile portion 36, so that when the door portion 24 (F, B) is opened , the breakage portion 27 is smoothly broken, and the opening performance of the door portion 24 (F, B) can be stabilized.

In addition, in the airbag cover 20 of the embodiment, the retainer 50 has a connection wall portion 53 that is connected to the mounting base 15 of the airbag device 10 that holds the folded airbag 11 at the peripheral edge portion 51 . configured as follows.

Therefore, in the embodiment, the arrangement area 22 of the door portions 24 (F, B) of the airbag cover 20 is arranged through the connection wall portion 53 extending from the peripheral edge portion 51 of the retainer 50, and the folded airbag in the airbag device 10 is arranged. Since it is connected to the mounting base 15 that holds the airbag 11, when the airbag 11 is inflated, the peripheral edge portion 51 of the retainer 50 is connected to the mounting base 15 of the airbag device 10 and separated from the mounting base 15 side. Therefore, the door portion 24 (F, B) connected to the peripheral edge portion 51 of the retainer 50 via the hinge portion 60 (F, B) absorbs the pressing force of the inflating airbag 11. It can be received accurately and opened quickly.

If the above points are not taken into consideration, the connecting wall portion 53 of the retainer 50 and the like may be connected to the surrounding member on the vehicle body side such as the instrument panel hose.

Furthermore, in the airbag cover 20 of the embodiment, the outer area of the hinge portion 60 (F, B) in the arrangement area 22 of the door portion 24 (F, B), that is, the front side collar portion 52a and the rear side collar portion 52b. The area includes the skin layer 62, the base material 32 (the front side portion 48a and the rear side portion 48b of the peripheral joint portion 48), and the retainer 50 (the front side flange portion 52a and the rear side flange portion 52b of the peripheral portion 51 of the retainer 50). A portion formed from three layers of is arranged.

Therefore, in the embodiment, even if the hinge portions 60 (F, B) of the retainer 50 are not connected to the base material 32 of the airbag cover body 31, the peripheral edge portion 51 of the retainer 50 is connected. Therefore, even if a strong tensile force is applied to the hinge portion 60 (F, B) of the retainer 50 when the door portion 24 (F, B) is opened, the vicinity of the hinge portion 60 (F, B) of the retainer 50 is The parts of the peripheral portion 51 (the front side flange portion 52a and the rear side flange portion 52b) are bonded to the base material 32 (the front side portion 48a and the rear side portion 48b of the peripheral bonding portion 48) and can be separated from the base material 32. Therefore, the door portion 24 (F, B) can be smoothly hinged without affecting the skin layer 62 or the like in the area of the general portion 21 of the airbag cover 20 where the retainer 50 is not provided. It can be opened while bending the portion 25 (the hinge portion 60 (F, B) of the retainer 50).

Further, in the airbag cover 20 of the embodiment, when the airbag 11 is inflated, the door portions 24 (F, B) are pushed by the inflating airbag 11 at the fragile portion 36 constituting the breaking portion 27, The breaking connecting portion 41A near the center portion 28a of the horizontal line portion 28, which is the starting point portion of the portion to be broken 27, is broken. The fracture connecting portion 41A is fractured due to stress concentration on the narrow side of the width dimension W12. At that time, the breaking connection portion 41A is formed on the front end portion 41b side with a narrow width dimension W12, leaving the base portion 41a side with a wide width dimension W11 that is close to the front end edge 35a of the door structure portion 35F of the door portion 24F on the front side. As shown in FIGS. 14A and 14B, the edge angle 41bb of the surface 32a of the base material 32 at the fracture surface 41ba on the side of the tip portion 41b having a narrow width dimension W12 is used as the door portion 24F. As the constituent portion 35F is opened, the hinge portion 60F is used as the center of rotation, and the back surface 62b of the skin layer 62 is brought into contact with the hinge portion 60F to push up the skin layer 62. As shown in FIG. That is, as shown in FIGS. 14A, 14B, and 14C, the breaking connecting portion 41A is connected to the leading end edge 35a of the door forming portion 35F of the door portion 24F, and the narrow leading end portion 41b side of the width dimension W12 is The edge corner 41bb of the door portion 35F bites into the skin layer 62 like a knife protruding from the leading edge 35a of the door-constituting portion 35F, so that the skin layer 62 can be smoothly broken. As a result, as the door-constituting portion 35F of the substrate 32 opens, the skin layer 62 is quickly broken from the leading edge 35a side of the door-constituting portion 35F. Together with the door portion 24B, the projection opening 68 of the airbag 11 is smoothly formed (see the two-dot chain line in FIG. 2). Since the door-constituting portion 35 does not have a protrusion or the like on the skin layer 62, the design of the surface 62a of the skin layer 62 is not affected.

Further, in the airbag cover 20 of the embodiment, the breakage connecting portion 41A near the center portion 28a of the horizontal line portion 28, which is the starting point of breakage, is formed at the tip end of which the width dimension W12 at both edges 42 and 43 in the width direction is reduced. Edges 42a and 43a on the side of portion 41b are connected to edges 39 on the side of breaking opening 37 to be connected so as to form an acute angle in plan view (see FIGS. 8 and 9).

Therefore, in the embodiment, the breaking connecting portion 41A near the central portion 28a serving as the starting point portion is connected to the edge 39 of the adjacent breaking opening at an acute angle on the side of the tip portion 41b that narrows the width dimension W12. Then, when the airbag 11 receives a tensile force due to the expansion of the airbag 11, the stress is smoothly concentrated on that portion, and the airbag 11 is easily ruptured. In addition, since the edges 42a and 43a on the fracture opening 37 side extending from the fractured distal end portion 41b were connected to the edge 39 on the fracture opening 37 side at an acute angle before fracture, At the time of breakage, as the front end portion 41b of the breakage connection portion 41A is pushed up, the back surface 62b of the skin layer 62 continues from the edge corner 41bb on the side of the broken end surface (fracture surface) 41ba of the front end portion 41b and is pushed and cut. , and the breakage from the breaking point due to the push-up of the tip portion 41b is easily propagated, and the skin layer 62 is smoothly broken from the vicinity of the center portion 28a, which is the starting point of the breakage, along the portion to be broken 27. can be made

Also, in the airbag cover 20 of the embodiment, as shown in FIG. The width of the side edges 42, 43 at the breaking connecting portion 41B away from the central portion 28a, with the crossing angle θA between the edges 42a, 43a of the narrow tip portion 41b and the edge 39 of the breaking opening 37 set to about 60°. The intersection angle θB between the edges 42a and 43a of the narrow tip portion 41b of dimension W22 and the edge 39 of the breaking opening 37 is about 75°, and the degree of acute angle is increased near the central portion 28a. Therefore, when the airbag 11 is inflated, stress tends to concentrate in the vicinity of the central portion 28a in the left-right direction of the horizontal line portion 28 where the breaking connecting portion 41A with the acute crossing angle θA is arranged, compared to other portions. , the breakage becomes easy to break, and the breakage starting point is accurately broken, and the door structure portion 35 (F, B) of the door portion 24 (F, B) rotates about the hinge portion 60 (F, B). , the tip edge 35a side can be smoothly rotated and opened.

In the embodiment, the angle of intersection between the edges 42a and 43a of the breaking connecting portions 41 (A, B) on the side of the tip portion 41b and the edge 39 of the breaking opening 37 is θA (approximately 60°). As two types of intersection angle θB (about 75°), the case where the small intersection angle θA is arranged on the side of the central portion 28a that is the starting point of fracture is shown. As long as the configuration is set as a part, the distal end portion 41b of the breaking connecting portion 41 may be arranged with the same acute angle of intersection over the entire horizontal line portion 28 . In addition, if at least one of the intersection angles θA and θB between the edges 42a and 43a of the side edges 42 and 43 of the breaking connecting portion 41 and the edge 39 of the breaking opening 37 is acute, Even if they are not equal, the other may be an obtuse angle of about 90°, and if both the intersection angle θA and the intersection angle θB are acute angles, they do not have to be equal to each other.

Further, as in the embodiment, when the sharp crossing angle is gradually increased as the distance from the fracture starting point (central portion 28a) side increases, in addition to two stages as in the embodiment, the fracture starting point The crossing angle may be set to be increased sequentially in multiple stages from the intersection angle near the site.

Further, the airbag cover 20 of the embodiment is arranged on the instrument panel 2 in front of the front seat of the vehicle 1 by arranging the wide base portion 41a side of the breaking connection portion 41 (A, B) on the front door portion 24F. It is configured as an airbag cover 20 provided.

Therefore, in the embodiment, when the door portions 24F and 24B are opened as the airbag 11 is inflated, the rupture connection portions 41A and 41B have width dimensions W12, Since the narrow distal end portion 41b side of W22 is broken, that is, in a state where the breaking connection portions 41A and 41B are coupled to the front door portion 24F side, and the breakage connection portion 41A is connected to the rear door portion 24b side. , 41B are not connected, the door portions 24F and 24B are opened (see the two-dot chain line in FIG. 2), and the door portion 24B on the rear side closer to the occupant is connected to the front edge 35a when opened. The parts 41A and 41B are opened without being joined together (see C in FIG. 14). Therefore, even if the rear door portion 24B comes into contact with an occupant when the rear door portion 24B is opened, the front edge 35a side with less unevenness can be brought into contact with the passenger.

In addition, in the embodiment, the door-constituting portion 35 (F, B) and the peripheral edge joint portion 48 of the base material 32 are substantially planar, and are coupled to the door support portion 58 (F, B) and the peripheral edge portion 51 of the retainer 50. 15 and 16, the airbag cover 20C shown in FIGS. It can be configured as In this airbag cover 20C, the base member 32C and the retainer 50C are integrally formed by two-color molding using a molding material, and the peripheral joint portions 48C on both left and right sides of the door structure portions 35 (F, B) of the base member 32C are formed. Fitting holes 48cb and 48db are formed in the left side portion 48c and the right side portion 48d, and a fitting convex portion 51a is formed in the peripheral portion 51 of the retainer 50C so as to be fitted into the fitting holes 48cb and 48db. It is configured. In the airbag cover main body 31C of the airbag cover 20C, the base material 32C and the retainer 50C are formed by two-color molding so that the fitting protrusions 51a are fitted into the fitting holes 48cb and 48db. The area (bonding area) is increased, and the bond strength (bonding strength) of the door support portion 58 (F, B) of the retainer 50C and the peripheral edge portion 51C to the substrate 32C can be improved.

Further, in the airbag cover 20 of the embodiment, the airbag cover main body 31 is integrally formed by two-color molding using the molding material of the base material 32 and the retainer 50 .

Therefore, in the embodiment, when the base material 32 and the retainer 50 are separately formed and adhered by vibration welding or the like to form the airbag cover main body, or insert-molded to form the airbag cover main body. Compared to this, it is possible to efficiently form the airbag cover main body 31 by reducing mold costs and man-hours. Of course, if this point is not taken into consideration, the base material 32 and the retainer 50 may be formed separately and bonded by vibration welding or the like to form the airbag cover main body, or the base material 32 or the retainer 50 may be pre-assembled. One of them may be molded first, and the molded product may be used as an insert for insert molding to form the airbag cover main body.

In addition, in the embodiment, the door portion of the airbag cover is configured to open to both the front and rear sides, but it may be a one-piece door portion that opens to the front side or the like. Further, as the door portion, the portion to be broken has a shape in which both ends of the horizontal line portion are opened in a Y shape. A four-door type with two on the left and right sides surrounded by .

DESCRIPTION OF SYMBOLS 10... Airbag apparatus, 11... Airbag, 15... Mounting base, 20, 20C... Airbag cover, 21... General part, 22... Door arrangement area, 24 (F, B)... Door part, 25... Hinge part , 27... Planned breaking portion, 31, 31C... Airbag cover main body, 32, 32C... Base material, 32a... Front surface, 32b... Back surface, 35 (F, B)... Door structure part, 36... Weak part, 47 (F , B)...space portion 48,48C...peripheral joint portion 50,50C...retainer 51,51C...peripheral edge portion 53...connecting wall portion 54...locking hole 58(F, B)...door support portion , 60 (F, B)... Hinge part 62... Skin layer 68... Opening for projection M1... Molding material (base material) M2... Molding material (retainer).

Claims (6)

When the airbag is inflated, it has a door portion that opens when pushed by the airbag so as to form an opening for projecting the airbag,
a synthetic resin base material arranged in an area including the door portion;
a retainer made of a synthetic resin that is softer than the base material and is coupled to the back side of the base material in the area where the door section is provided;
wherein the door portion includes a door-constituting portion of the base material and a door supporting portion provided on the retainer and holding the door-constituting portion;
The retainer includes the door support portion, a peripheral portion provided around the door support portion, and the retainer provided between the peripheral portion and the door support portion so as to be bent when the door portion is opened. An airbag cover comprising a substantially flat hinge portion,
an airbag cover body comprising the base material and the retainer;
a skin layer adhered to the surface side of the airbag cover body and having flexibility that can be broken when the door is opened;
configured with
A space is provided in a portion where the base material is provided with the hinge portion of the retainer as a non-arranged portion of the base material,
An airbag cover, wherein the area of the hinge portion is composed of two layers, the hinge portion of the retainer and the skin layer adhered to the hinge portion. The door portion is composed of three layers in which the skin layer, the door-constituting portion of the base material, and the door supporting portion of the retainer are arranged from the outer surface side. The airbag cover according to claim 1. A portion to be broken that is pushed by the inflating airbag and broken is provided around the door portion excluding the portion where the hinge portion is provided,
Claim 1 or Claim 2, wherein the portion to be broken is composed of two layers of the skin layer and the base material provided with a weakened portion as a portion where the retainer is not provided. The airbag cover described in . 3. The retainer is configured such that a connecting wall portion connected to a mounting base of an airbag device that holds the folded airbag is provided on the peripheral edge portion of the retainer. The airbag cover according to any one of claims 3 to 4. A part formed of three layers of the skin layer, the base material, and the retainer is arranged in an area outside the hinge part in the arrangement area of the door part. The airbag cover according to any one of claims 1 to 4. 6. The airbag cover body according to any one of claims 1 to 5, wherein the airbag cover body is integrally formed by two-color molding using molding materials for the base material and the retainer. airbag cover.

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