Driver's airbag device

Abstract

The present invention aims to provide a driver's seat safety airbag device that can properly protect the head by catching the head of the occupant through the expansion and deployment of an airbag cushion and suppressing the rotation of the occupant's head. The driver's seat safety airbag device (100) comprises: a passenger side panel (118) having a larger area than a steering side panel (116) of the airbag cushion (104); a side panel (120) forming the side of the airbag cushion; the passenger side panel including a recessed portion (128) recessed toward the steering wheel (108) side and an annular bulging portion (130) located around the recessed portion, and being stretched to the steering side by a predetermined means, so that a central area (140) closest to the steering wheel and a first inclined area (142) gradually extending from the central area to the occupant side are formed in the recessed portion, and a second inclined area (144) connected to the first inclined area and gradually extending is formed in the bulging portion, and the occupant's head is restrained by the central area, the first inclined area, and the second inclined area.

Description

Technical Field

[0001] The present invention relates to a driver's seat safety airbag device, which includes an airbag cushion for restraining an occupant in an emergency. Background Art

[0002] At present, the steering wheel of a vehicle is generally equipped with a driver's seat airbag device as a standard. The driver's seat airbag device is a safety device that is activated in an emergency such as a vehicle collision, and uses gas pressure to inflate and deploy the airbag cushion to catch the occupant for protection. The airbag cushion of the driver's seat airbag device is stored in the steering wheel together with the inflator, and is inflated and deployed between the steering wheel and the occupant of the driver's seat by the gas supplied from the inflator (for example, Patent Document 1).

[0003] Patent Document 1 describes an airbag device for a steering wheel of an automobile. In the airbag device for a steering wheel, a portion of the airbag cushion has a chest depression that is depressed on the steering wheel side. When the airbag cushion is inflated, the chest depression faces the chest of the occupant to be protected. In Patent Document 1, during a collision between the occupant and the airbag cushion, the chest depression of the airbag cushion minimizes the load applied to the chest of the occupant, thereby effectively restraining the head of the occupant.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Publication No. 2013-529577 Summary of the invention

[0007] Problem that the invention aims to solve

[0008] In recent years, with the introduction of the North American New Car Assessment Program (NCAP), standards for brain injury (BrIC, Brain Injury Criterion) have been set. This head and brain disorder is greatly affected by the rotation of the occupant's head, especially the angular velocity. The steering wheel airbag device of Patent Document 1 only suppresses the occupant's head by reducing the load applied to the occupant's chest through the chest depression of the airbag cushion. Therefore, there is room for improvement in suppressing the rotation of the head that has a great impact on head and brain disorders.

[0009] The present invention has been made in view of such a problem, and an object of the present invention is to provide an airbag device for a driver's seat which can appropriately protect the head by catching the head of the occupant with an airbag cushion when inflated and deployed and suppressing rotation of the head of the occupant.

[0010] Solutions to the problem

[0011] In order to solve the above-mentioned problems, the representative structure of the driver's seat airbag device involved in the present invention is as follows: a driver's seat airbag device comprises: an inflator, which is stored in the steering wheel of the vehicle; an airbag cushion, which is stored in the steering wheel together with the inflator and is inflated and deployed between the steering wheel and the occupant of the driver's seat by using the gas supplied from the inflator, characterized in that the airbag cushion comprises: a steering side panel, which is located on the steering wheel side; a passenger side panel, which is located on the passenger side and has a larger area than the steering side panel; and a side panel, which connects the steering side panel and the passenger side panel to form an airbag cushion. On the side of the bladder, the passenger side panel includes: a recessed portion, which is recessed toward the steering wheel side; an annular bulging portion, which is located around the recessed portion and bulges toward the passenger side, and is pulled toward the steering side by a predetermined means at a predetermined position of the passenger side panel, thereby forming a central area closest to the steering wheel and a first inclined area that is gradually inclined from the central area toward the passenger side in a spreading shape, and a second inclined area is formed in the bulging portion, which is connected to the first inclined area and is gradually inclined toward the passenger side, and the head of the passenger is restrained by the central area, the first inclined area, and the second inclined area.

[0012] In the above structure, the shape of the airbag cushion is such that the passenger side panel that forms the central area, the first inclined area, and the second inclined area for restraining the occupant when inflated and deployed is wider, and the steering side panel that receives the reaction force from the steering wheel is narrower. The airbag cushion also ensures a predetermined thickness from the steering wheel side to the passenger side through the side panel. Therefore, the airbag cushion has a predetermined thickness when inflated and deployed, and the central area, the first inclined area, and the second inclined area for restraining the occupant can be ensured by the wider passenger side panel.

[0013] Here, with the introduction of the North American New Car Assessment Program (NCAP), the standard of Brain Injury Criterion (BrIC) was set. This brain injury is greatly affected by the rotation of the occupant's head, especially the angular velocity. Therefore, in the passenger side panel of the above structure, a first inclined area and a second inclined area are formed by a recessed portion recessed toward the steering wheel side and an annular bulge located around the recessed portion, which are inclined surfaces gradually expanding toward the occupant side to restrain the occupant. Therefore, the central area of ​​the recessed portion in the passenger side panel of the airbag cushion catches the occupant's head, and the first inclined area and the second inclined area are inclined gradually expanding from the central area of ​​the recessed portion toward the occupant side, thereby suppressing the rotation of the occupant's head and appropriately protecting the head.

[0014] The central area of ​​the recessed portion may be located on the rotation axis of the steering wheel. Thus, in the airbag cushion, since the recessed portion of the passenger side panel receives the force from the passenger's head at the rotation axis of the steering wheel during expansion and deployment, the impact absorption energy does not slip out. Therefore, the airbag cushion can more reliably receive and protect the passenger's head.

[0015] When the recessed portion is observed from the passenger side to the steering wheel side, the recessed portion may be symmetrical in shape in the vertical direction and in the left-right direction. In addition, the so-called "when the recessed portion is observed from the passenger side to the steering wheel side" refers to, for example, when the recessed portion is observed in a plane orthogonal to the rotation axis of the steering wheel of the recessed portion. Thus, in the airbag cushion, no matter when the passenger's head enters the recessed portion of the passenger side panel from any direction, such as up, down, left, or right, during expansion and deployment, the passenger's head can be reliably received by the recessed portion, and the head can be stably restrained. Examples of the outer peripheral shape of the recessed portion here include circular, elliptical, square, rectangular, and the like.

[0016] When the recessed portion is viewed from the passenger side toward the steering wheel side, the size in the vertical direction and the size in the horizontal direction may be the same shape. Thus, in the airbag cushion, no matter the passenger's head enters the recessed portion of the passenger side panel from any direction, vertically, horizontally, or horizontally during expansion and deployment, the passenger's head can be reliably received by the recessed portion, and the head can be stably restrained. Examples of the outer peripheral shape of the recessed portion include a circle, a square, and the like.

[0017] When the recessed portion is viewed from the passenger side toward the steering wheel side, the vertical dimension may be longer than the horizontal dimension. Here, the vertical position where the passenger's head abuts against the recessed portion of the passenger side panel varies depending on the passenger's physique. In the above structure, since the outer peripheral shape of the recessed portion is a longitudinally long shape, even if the passenger's physique is larger or smaller than the standard, the recessed portion can be used to receive the passenger's head and restrain the passenger.

[0018] When the recessed portion is viewed from the passenger side toward the steering wheel side, the size in the vertical direction may be shorter than the size in the horizontal direction. Thus, the outer peripheral shape of the recessed portion becomes a horizontally long shape. Therefore, when a collision such as a force in a rotational direction is applied to the vehicle occurs, even if the passenger's head enters from the left or right direction, the recessed portion can reliably receive the passenger's head, and the head can be stably restrained.

[0019] A vertical line perpendicularly intersecting the first inclined area and the second inclined area of ​​the passenger side panel of the airbag cushion may intersect the side panel. According to the shape of the airbag cushion, even if the head of the passenger enters the first inclined area and the second inclined area in any entry direction, the side panel is almost always present on the extension line of the entry direction. Therefore, the airbag cushion has a thickness from the steering wheel side to the passenger side, and can receive the head of the passenger entering the first inclined area and the second inclined area to absorb the impact, thereby suppressing the rotation of the head and appropriately protecting the head.

[0020] The above-mentioned prescribed means include: a pair of main tethers, which are located inside the airbag cushion, mounted between the steering side panel and the passenger side panel, and have a size that is tensioned when the airbag cushion is inflated and deployed to pull the passenger side panel toward the steering side; a pair of secondary tethers, which are located inside the airbag cushion, mounted between the middle portion of the pair of main tethers and the passenger side panel, and have a size that is tensioned when the airbag cushion is inflated and deployed to pull the passenger side panel toward the middle portion of the pair of main tethers, the pair of main tethers are separated from each other in the passenger side panel and are respectively combined with the edges of the recessed portion, and the pair of secondary tethers are separated from each other and are respectively combined at positions on the inner side of the edges of the recessed portion in the passenger side panel, and the size from the middle portion of the pair of main tethers to the passenger side panel can be longer than the size of the pair of secondary tethers.

[0021] In this way, the pair of main tethers are respectively coupled to the edge of the recessed portion of the passenger side panel, that is, the boundary between the recessed portion and the bulging portion, and the pair of auxiliary tethers are respectively coupled to the inner side of the edge of the recessed portion, thereby forming the first inclined area and the second inclined area. Furthermore, a central area closest to the steering wheel and not inclined is formed between the pair of auxiliary tethers in the recessed portion.

[0022] The width of the pair of main tethers may be wider than the width of the pair of auxiliary tethers. Thus, in the passenger side panel, a central area of ​​a recessed portion for receiving the passenger's head, a first inclined area of ​​the recessed portion for suppressing the rotation of the passenger's head, and a second inclined area of ​​the bulging portion can be formed by a pair of wide main tethers and a pair of narrow auxiliary tethers.

[0023] The pair of main tethers and the pair of auxiliary tethers can be arranged side by side in the vehicle width direction or the vehicle up-down direction. Thus, by arranging the pair of main tethers and the pair of auxiliary tethers side by side in the vehicle width direction or the vehicle up-down direction, the central area, the first inclined area and the second inclined area can be reliably formed on the passenger side panel.

[0024] The first inclined area and the second inclined area may be inclined at an angle of 10° or more relative to a reference plane orthogonal to the rotation axis of the steering wheel. In this way, since the first inclined area and the second inclined area that restrain the occupant are inclined at an angle of 10° or more relative to the reference plane, the airbag cushion receives the occupant's head through the central area formed by the occupant side panel and the first inclined area and the second inclined area, and at the same time reduces the angular velocity accompanying the rotation of the occupant's head, thereby suppressing head and brain injuries. In addition, if the inclination angle of the first inclined area and the second inclined area is less than 10°, especially less than 5°, the angular velocity of the head becomes large, and it may be difficult to suppress head and brain injuries.

[0025] Effects of the Invention

[0026] According to the present invention, it is possible to provide an airbag device for a driver's seat that can receive the head of an occupant by an inflated and deployed airbag cushion and can suppress rotation of the occupant's head to appropriately protect the head. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram illustrating a driver's seat airbag device in an embodiment of the present invention.

[0028] Figure 2 This is an example of viewing from other directions. Figure 1 (b) is a diagram showing the state of the driver's seat airbag device.

[0029] Figure 3 It is an example Figure 2 (a) is a diagram showing details of the driver's airbag device.

[0030] Figure 4 It is a diagram illustrating a driver's seat airbag device in a comparative example.

[0031] Figure 5 The diagram exemplifies evaluation of the driver's seat airbag device in the present embodiment and the driver's seat airbag device of a comparative example.

[0032] Figure 6 It is an example Figure 1 (b) is a diagram of a modified example of the airbag cushion. DETAILED DESCRIPTION

[0033] Below, the preferred embodiments of the present invention are described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values ​​shown in the above embodiments are only examples for facilitating the understanding of the present invention, and do not limit the present invention unless otherwise specified. In addition, in this specification and the accompanying drawings, for elements having substantially the same function and structure, repeated descriptions are omitted by marking the same symbols, and elements that are not directly related to the present invention are omitted from the drawings.

[0034] Figure 1 1 is a schematic diagram illustrating a driver-seat airbag device 100 in an embodiment of the present invention. Figure 1 (a) shows a vehicle 102 before the driver's airbag device 100 is activated. Figure 1 (b) illustrates a state in which the airbag cushion 104 of the driver's seat airbag device 100 is inflated and deployed.

[0035] In the present embodiment, when the passenger sits on the seat in a normal posture, the direction the passenger is facing is called the front, and the opposite direction is called the rear. In addition, when the passenger sits on the seat in a normal posture, the right side of the passenger is called the right direction, and the left side of the passenger is called the left direction. Furthermore, when the passenger sits on the seat in a normal posture, the direction of the passenger's head is called the top, and the direction of the passenger's waist is called the bottom. In addition, in the drawings used in the following description, the front, back, left, right, up and down directions based on the above-mentioned passenger are expressed as Front, Back, Left, Right, Up, Down as needed.

[0036] In addition, in the present embodiment, the driver's seat airbag device 100 is implemented as a device for the driver's seat in a vehicle with the steering wheel on the left side, that is, the front left vehicle seat 106. In the following description, for example, the vehicle outer side in the vehicle width direction (hereinafter referred to as the vehicle outer side) refers to the vehicle left side, and the vehicle inner side in the vehicle width direction (hereinafter referred to as the vehicle inner side) refers to the vehicle right side.

[0037] The airbag cushion 104 of the driver's seat airbag device 100 is stored in a folded or rolled state in the center of a hub 110 at a front position of a vehicle seat 106. The hub 110 includes a housing (not shown) for storing the airbag cushion 104, a cover 112, and the like. An inflator 114 (see FIG. 1 ) is stored inside the hub 110 together with the airbag cushion 104. Figure 3 (a)).

[0038] The airbag cushion 104 begins to expand while rupturing the cover portion 112 using the gas from the inflator 114, and expands in a bag-like manner forward of the seat position of the vehicle seat 106, restraining the upper body and head of the occupant who wants to move forward. That is, the airbag cushion 104 expands and expands between the occupant sitting on the vehicle seat 106 and the steering wheel 108. In addition, if Figure 1 As shown in (b), the airbag cushion 104 has a circular shape when viewed from the seated position side, and is formed by overlapping a plurality of panels (described later) constituting the surface thereof and sewing or bonding them.

[0039] Figure 2 This is an example of viewing from other directions. Figure 1(b) is a diagram showing a state of the driver's airbag device 100 . Figure 2 (a) shows the rear view from the outside of the vehicle. Figure 1 (b) is a perspective view of the state of the airbag cushion 104 and the steering wheel 108. Figure 2 (b) Yes Figure 2 (a) is a cross-sectional view of the airbag cushion 104 taken along the line AA.

[0040] like Figure 2 As shown in FIGS. 2(a) and 2(b), the airbag cushion 104 when inflated and deployed has a shape close to a truncated cone whose diameter increases from the steering wheel 108 side toward the passenger side (the rear side of the vehicle). The airbag cushion 104 has a steering side panel 116 (see FIG. 2(a) and FIG. 2(b)). Figure 2 (b)), passenger side panel 118 and side panel 120.

[0041] Figure 3 It is an example Figure 2 (a) is a diagram showing details of the driver's airbag device 100. Figure 3 (a) is through Figure 2 (a) is a diagram schematically illustrating the internal structure of the airbag cushion 104 by means of each panel. In order to further illustrate the internal structure, the airbag cushion 104 is shown as viewed from an oblique upper direction. Figure 3 (b) and 3(c) illustrate the Figure 2 (b) is a state in which the steering side panel 116 and the passenger side panel 118 of the airbag cushion 104 are deployed on a plane.

[0042] The steering side panel 116 is a panel located on the side of the steering wheel 108. Figure 3 As shown in (b), the steering side panel 116 is circular and functions as a reaction force surface to receive a reaction force from the steering wheel 108 when the airbag cushion 104 is inflated and deployed. Since the airbag cushion 104 is inflated and deployed in a truncated cone shape extending toward the passenger side, the area of ​​the steering side panel 116 is larger than that of the passenger side panel 118 (see FIG. Figure 3 (c)) is narrow. In addition, a fixing area 122 is formed in the center of the steering side panel 116. The fixing area 122 is for inserting the inflator 114 (refer to Figure 3 (a)) and fixed to the area inside the hub 110 of the steering wheel 108.

[0043] The inflator 114 is a device for supplying gas, and in the present embodiment, a disc-shaped (disc-shaped) inflator is used. A portion of the inflator 114 having a gas outlet 123 is inserted into the airbag cushion 104 from a fixed region 122 of the steering side panel 116. The inflator 114 operates in response to an impact detection signal transmitted from a sensor not shown in the figure, and supplies gas to the airbag cushion 104 from the gas outlet 123. A plurality of studs 124 are provided on the inflator 114. The studs 124 penetrate the fixed region 122 of the steering side panel 116 of the airbag cushion 104, and are fastened to the hub 110 of the steering wheel 108 (see FIG. 1 ). Figure 1 By fastening the stud 124 , the airbag cushion 104 is also fixed inside the wheel hub 110 .

[0044] In addition, currently popular inflators include a type that is filled with a gas generating agent and burns to generate gas, a type that is filled with compressed gas and supplies gas without generating heat, or a hybrid type that uses both combustion gas and compressed gas. As the inflator 114 of this embodiment, any type of inflator can be used.

[0045] like Figure 3 As shown in (c), the passenger side panel 118 located on the passenger side is circular and functions as a passenger restraint surface (described later) for restraining the passenger when the airbag cushion 104 is inflated and deployed. In addition, as described above, since the airbag cushion 104 is inflated and deployed in a truncated cone shape extending toward the passenger side, the passenger side panel 118 is configured to have an area larger than the steering side panel 116 (see Figure 3 (b)) large. Figure 2 (a) and Figure 2 As shown in (b), the side panel 120 connects the steering side panel 116 and the passenger side panel 118 to form the side of the airbag cushion, thereby ensuring a predetermined thickness of the airbag cushion 104 from the steering wheel 108 side to the passenger side.

[0046] In recent years, with the introduction of the North American New Car Assessment Program (NCAP), the standard of brain injury (BrIC) has been set. This brain injury is greatly affected by the rotation of the occupant's head, especially the angular velocity. Therefore, the driver's seat airbag device 100 of this embodiment adopts an airbag cushion 104 that is inflated and deployed to not only catch the occupant's head 126 (see Figure 2 (b)), and the rotation of the head 126 is suppressed, and the structure of the head 126 is appropriately protected.

[0047] Specifically, if Figure 2 (a) and Figure 2As shown in (b), the passenger side panel 118 of the airbag cushion 104 includes a recessed portion 128 and a bulging portion 130. The recessed portion 128 is a portion that is recessed toward the steering wheel 108. The bulging portion 130 is an annular portion that is located around the recessed portion 128 and bulges toward the passenger side.

[0048] In the airbag cushion 104, the passenger side panel 118 is provided by means of a predetermined Figure 2 (b) and Figure 3 The pair of main tethers 132, 134 and the pair of auxiliary tethers 136, 138 shown in (a) are pulled toward the turning side. Figure 2 (b) and Figure 3 The recessed portion 128 shown in (a) is formed with a central region 140 and a first inclined region 142 , and further, a second inclined region 144 is formed in the bulging portion 130 .

[0049] The central region 140 of the recessed portion 128 is the region of the passenger side panel 118 closest to the steering wheel 108, such as Figure 2 (b) is located on the rotation axis B of the steering wheel 108. The first inclined region 142 of the recessed portion 128 is an area that is gradually inclined from the central region 140 toward the passenger side. The second inclined region 144 of the bulging portion 130 is an area that is connected to the first inclined region 142 and is gradually inclined toward the passenger side.

[0050] In the airbag cushion 104, a so-called passenger restraint surface 146 for restraining the passenger's head 126 is formed by the central region 140, the first region 142, and the second region 144 of the passenger side panel 118. When restraining the passenger's head 126, in the airbag cushion 104, the passenger's head 126 is received by the central region 140 of the recessed portion 128 in the passenger restraint surface 146, and the rotation of the passenger's head 126 is suppressed by the first inclined region 142 and the second inclined region 144 which are inclined in a gradually expanding shape from the central region 140 of the recessed portion 128 toward the passenger side.

[0051] Since the central area 140 is located on the rotation axis B of the steering wheel 108, the concave portion 128 of the passenger side panel 118 receives the force received from the passenger's head 126 by the rotation axis B of the steering wheel 108 when the airbag cushion 104 is inflated and deployed, so the impact absorption energy does not slip away. Therefore, the airbag cushion 104 can more reliably receive and protect the passenger's head 126.

[0052] In addition, in the airbag cushion 104, Figure 2(b) The distance La from the central region 140 of the recessed portion 128 to the steering side panel 116 in contact with the hub 110 of the steering wheel 108 is somewhat equal to the diameter Lb of the occupant restraining surface 146 formed by the central region 140, the first inclined region 142, and the second inclined region 144. In addition, the diameter Lb of the occupant restraining surface 146 is a distance in a direction perpendicular to the rotation axis B of the steering wheel 108. In this way, in the airbag cushion 104, since the distance La and the diameter Lb are somewhat equal, when the recessed portion 128 receives the occupant's head 126, a thickness sufficient to suitably protect the head 126 is ensured.

[0053] like Figure 2 (b) and Figure 3 As shown in (a), a pair of main tethers 132, 134 are located inside the airbag cushion 104 and are spanned between the steering side panel 116 and the passenger side panel 118. The pair of main tethers 132, 134 have a size that is stretched when the airbag cushion 104 is inflated and deployed to pull the passenger side panel 118 toward the steering wheel 108. In addition, one end portions 148, 150 of the pair of main tethers 132, 134 are connected to the steering side panel 116.

[0054] A pair of secondary tethers 136, 138 are located inside the airbag cushion 104 and are mounted on the pair of primary tethers 132, 134. Figure 2 (b) and the passenger side panel 118. The pair of secondary tethers 136, 138 have a size that is stretched when the airbag cushion 104 is inflated and deployed to pull the passenger side panel 118 toward the middle portion 152, 154 of the pair of main tethers 132, 134. In addition, one end portion 156, 158 (see Figure 3 (a)) with the main straps 132, 134 Figure 2 (b) shows the intermediate parts 152 and 154 being combined.

[0055] Here, the other ends 160, 162 (see Figure 3 (a)) are separated from each other and are respectively connected to the passenger side panel 118 Figure 2 (a) and Figure 2 (b) The edges 164 and 166 of the recessed portion 128 are joined. In addition, the other ends 168 and 170 of the pair of auxiliary straps 136 and 138 (see Figure 2 (b) and Figure 3 (a)) are separated from each other and respectively connected to the inner sides of the edges 164, 166 of the recessed portion 128 in the passenger side panel 118. Figure 2As shown in (b), the dimension Lc from the middle portion 152, 154 of a pair of main straps 132, 134 to the other end 160, 162, i.e., the edge 164, 166 of the recessed portion 128 of the passenger side panel 118, is longer than the dimension Ld from one end 156, 158 of a pair of secondary straps 136, 138 to the other end 168, 170.

[0056] Thus, in the airbag cushion 104, the pair of main tethers 132 and 134 as the regulating means are respectively coupled to the edges 164 and 166 of the recessed portion 128 of the passenger side panel 118, that is, the boundary between the recessed portion 128 and the bulging portion 130. In addition, in the airbag cushion 104, the pair of secondary tethers 136 and 138 as the regulating means are respectively coupled to the inner sides of the edges 164 and 166 of the recessed portion 128.

[0057] Thus, the airbag cushion 104 tightens the passenger side panel 118 toward the turning side by a predetermined means, thereby forming the first inclined region 142 and the second inclined region 144. In addition, a central region 140 that is closest to the steering wheel 108 and is not inclined and is close to a plane is formed between the pair of secondary tethers 136 and 138 in the recessed portion 128. In addition, an occupant restraint surface 146 is formed including the central region 140, the first inclined region 142, and the second inclined region 144, but the inclination of the central region 140 does not necessarily have to be close to a plane as long as it is gentler than that of the first inclined region 142 and the second inclined region 144.

[0058] In addition, if Figure 2 (b) and Figure 3 As shown in (a), a pair of main tethers 132, 134 and a pair of auxiliary tethers 136, 138 are arranged in parallel in the vehicle width direction. Thus, in the airbag cushion 104, an occupant restraint surface 146 including a central area 140, a first inclined area 142, and a second inclined area 144 can be reliably formed on the passenger side panel 118. However, the pair of main tethers 132, 134 and a pair of auxiliary tethers 136, 138 are not limited to the vehicle width direction, and can also be arranged in parallel in the vehicle up-down direction. In this way, the occupant restraint surface 146 can also be formed on the passenger side panel 118.

[0059] The width of the pair of main tethers 132 and 134 is wider than the width of the pair of secondary tethers 136 and 138. Therefore, in the passenger side panel 118, the passenger restraint surface 146 can be formed by the pair of wide main tethers 132 and 134 and the pair of narrow secondary tethers 136 and 138.

[0060] Here, the inclination of the first inclined region 142 and the second inclined region 144 will be described. Figure 2(b) shows an example of a junction C, a tangent line D, and a reference plane E. The junction C is a point where the occupant's head 126 contacts the second inclined region 144 of the occupant restraint surface 146 in the predetermined entry direction indicated by the arrow F. The tangent line D is a line along the inclination of the first inclined region 142 and the second inclined region 144. The reference plane E is a plane orthogonal to the rotation axis B of the steering wheel 108, which is shown by a line. In the present embodiment, the angle of the tangent line D relative to the reference plane E is referred to as the restraint surface angle ωz.

[0061] exist Figure 2 (b) also illustrates a vertical line G and an extended line H. The vertical line G is a line passing through the junction C and perpendicularly intersecting the tangent line D. The extended line H is a line passing through the junction C along the entry direction indicated by the arrow F. In the airbag cushion 104, the vertical line G intersects the side panel 120 at the intersection I. According to the shape of the airbag cushion 104, even if the occupant's head 126 enters the first inclined region 142 and the second inclined region 144 in any entry direction, the side panel 120 is almost always present on the extended line H in the entry direction as indicated by the intersection J.

[0062] Therefore, the airbag cushion 104 has a thickness from the steering wheel 108 side to the occupant side, and can receive the occupant's head 126 entering the first inclined region 142 and the second inclined region 144 to absorb the impact, suppress the rotation of the head 126 , and appropriately protect the head 126 .

[0063] The inventors have found that the larger the restraint surface angle ωz of the airbag cushion 104 is, the smaller the rotation, i.e., the angular velocity, of the occupant's head 126 is, and thus the head and brain damage can be suppressed. Figure 4 A Free Fright Impactor evaluation (CAE) was performed on the driver's seat airbag device 200 of the illustrated comparative example.

[0064] Figure 4 FIG. 2 is a diagram illustrating a driver-seat airbag device 200 according to a comparative example. Figure 4 (a) illustrates a state where the airbag cushion 202 of the driver's seat airbag device 200 is inflated and deployed. Figure 4 (b) Yes Figure 4 (a) is a KK cross-sectional view of the airbag cushion 202.

[0065] The airbag cushion 202 has a pair of inner ties 208 and 210 between the steering side panel 204 and the passenger side panel 206, and the thickness is ensured by connecting the steering side panel 204 and the side panel 212 of the passenger side panel 206. However, the passenger side panel 206 of the airbag cushion 202 does not have the recessed portion 128 and the bulged portion 130 of the airbag cushion 104, and a protruding portion 214 protruding toward the passenger side is formed between the pair of inner ties 208 and 210. Therefore, in the airbag cushion 202 of the comparative example, as shown in FIG. Figure 4 As shown in (b), the occupant's head 126 is received by the protruding portion 214, and the restraint surface angle ωz becomes smaller.

[0066] Figure 5 1 is a diagram showing evaluation of the driver's seat airbag device 100 in the present embodiment and the driver's seat airbag device 200 in the comparative example. In the graph in the figure, the vertical axis is the angular velocity (deg / s) of the head 126, and the horizontal axis is time (ms). In the graph, the measured value of the airbag cushion 104 in the present embodiment is shown by a solid line, and the measured value of the airbag cushion 202 in the comparative example is shown by a dotted line. Then, the evaluation is performed while changing the restraint surface angle ωz.

[0067] As a result, when the constraint surface angle ωz is less than 10°, especially less than 5°, as shown by the dotted line in the graph, the angular velocity of the head 126 increases significantly, making it difficult to suppress head brain damage. On the other hand, when the constraint surface angle ωz is greater than 10°, as shown by the solid line in the graph, the angular velocity of the head 126 can be reduced, and head brain damage can be suppressed.

[0068] In the driver's seat airbag device 100 of the present embodiment, the restraint surface angle ωz of the first inclined region 142 and the second inclined region 144 in the passenger restraint surface 146 of the airbag cushion 104 is set to be greater than 10°. Therefore, the airbag cushion 104 receives the passenger's head 126 through the central region 140 formed by the passenger side panel 118, and suppresses the rotation of the passenger's head 126 through the first inclined region 142 and the second inclined region 144, reduces the angular velocity, and thus can suppress head and brain damage.

[0069] Figure 6 It is an example Figure 1 (b) is a diagram of a modified example of the airbag cushion 104. Figure 1 (b) Figure 6 In the airbag cushion 104, 104A shown in (a), when the recessed portion 128, 128A is viewed from the passenger side toward the steering wheel 108 side, for example, when the recessed portion 128, 128A is at the rotation axis B of the steering wheel 108 (refer to Figure 2(b)) When viewed on a plane orthogonal to the plane, the outer peripheral shapes of the recessed portions 128 and 128A are respectively circular and square, that is, symmetrical in the vertical direction and symmetrical in the horizontal direction, and the size in the vertical direction is the same as the size in the horizontal direction. Therefore, in the airbag cushion 104 and 104A, even if the occupant's head 126 enters the recessed portion 128 and 128A of the occupant side panel 118 and 118A from any direction of the vertical direction or the horizontal direction during inflation and deployment, the occupant's head 126 can be reliably received by the recessed portion 128 and 128A, and the head 126 can be stably restrained. In addition, the airbag cushion 104A is Figure 6 The recessed portion 128A shown in (a) forms a central area 140A and a first inclined area 142A, and further forms a second inclined area 144A in the bulging portion 130A. Through these areas, the rotation of the head 126 of the occupant can be suppressed while catching the head 126, and brain damage can be suppressed.

[0070] exist Figure 6 (b) Figure 6 In the airbag cushions 104B and 104C shown in (c), the outer peripheral shapes of the recessed parts 128B and 128C are respectively a horizontally long rectangle and an ellipse, that is, vertically symmetrical and horizontally symmetrical, and further, the vertical dimension is shorter than the horizontal dimension. Therefore, in the airbag cushions 104B and 104C, when a collision such as a force in a rotational direction is applied to the vehicle occurs, even if the head 126 of the occupant enters from the left and right directions, the recessed parts 128B and 128C of the occupant side panels 118B and 118C can reliably receive the head 126 and stably restrain the head 126. In addition, the airbag cushions 104B and 104C form central areas 140B and 140C and first inclined areas 142B and 142C in the recessed portions 128B and 128C, and further form second inclined areas 144B and 144C in the bulging portions 130B and 130C. These areas can receive the occupant's head 126 while suppressing rotation of the head 126, thereby suppressing brain damage.

[0071] exist Figure 6 (d) Figure 6In the airbag cushions 104D and 104E shown in (e), the outer peripheral shapes of the recessed parts 128D and 128E are respectively long rectangles and ellipses, that is, they are vertically symmetrical and horizontally symmetrical, and further, the dimensions in the vertical direction are longer than the dimensions in the horizontal direction. Here, the vertical position where the head 126 of the occupant abuts against the recessed parts 128D and 128E of the occupant side panels 118D and 118E varies according to the physique of the occupant. In the airbag cushions 104D and 104E, since the outer peripheral shapes of the recessed parts 128D and 128E are long, even if the physique of the occupant is larger or smaller than the standard, the head 126 of the occupant can be received and restrained by the recessed parts 128D and 128E. In addition, the airbag cushions 104D and 104E form central areas 140D and 140E and first inclined areas 142D and 142E in the recessed portions 128D and 128E, and further form second inclined areas 144D and 144E in the bulging portions 130D and 130E. These areas can receive the occupant's head 126 while suppressing rotation of the head 126, thereby suppressing brain damage.

[0072] In addition, the outer peripheral shapes of the recessed portions 128, 128A, 128B, 128C, 128D, and 128E are circular, square, vertically long rectangle and elliptical, horizontally long rectangle and elliptical as described above, but are not limited to these. As long as the occupant's head 126 can be reliably received, it can also be an appropriate shape that is symmetrical in the upper and lower parts and symmetrical in the left and right parts.

[0073] The preferred embodiments of the present invention are described above with reference to the accompanying drawings, but it goes without saying that the present invention is not limited to the examples involved. It is obvious that those skilled in the art can think of various changes or modifications within the scope of the claims, which of course also belong to the technical scope of the present invention.

[0074] In the above embodiment, an example in which the driver's airbag device 100 of the present invention is applied to an automobile is described. However, the airbag device 100 may be applied to aircraft, ships, etc. other than automobiles, and the same effects may be obtained.

[0075] Industrial Applicability

[0076] The present invention can be used in a driver's seat airbag device including an airbag cushion for restraining an occupant in an emergency.

[0077] Explanation of symbols

[0078] 100, 200…Driver's airbag device

[0079] 102…Vehicles

[0080] 104, 104A, 104B, 104C, 104D, 104E, 202…airbag cushion

[0081] 106 ... Vehicle seat 108 ... Steering wheel

[0082] 110 ... hub 112 ... cover

[0083] 114…Inflator

[0084] 116, 204… Turn to side panel

[0085] 118, 118A, 118B, 118C, 118D, 118E, 206… Passenger side panel

[0086] 120, 212…Side panel 122…Fixed area

[0087] 123…Gas outlet 124…Stud

[0088] 126…Occupant’s head

[0089] 128, 128A, 128B, 128C, 128D, 128E ... recessed portion

[0090] 130, 130A, 130B, 130C, 130D, 130E…bulge

[0091] 132, 134... Main laces 136, 138... Secondary laces

[0092] 140, 140A, 140B, 140C, 140D, 140E…Central area

[0093] 142, 142A, 142B, 142C, 142D, 142E ... first inclined region

[0094] 144, 144A, 144B, 144C, 144D, 144E ... second inclined region

[0095] 146…Occupant restraint surface

[0096] 148, 150…One end of the main tether

[0097] 152, 154…Middle

[0098] 156, 158…One end of the auxiliary tether

[0099] 160, 162…The other end of the auxiliary lace

[0100] 164, 166…Edge of the concave portion

[0101] 168, 170…The other end of the secondary lace

[0102] 208, 210...Inner lace 214...Protrusion

Claims

1. A driver's seat airbag device, comprising: an inflator housed in the steering wheel of the vehicle; an airbag cushion which is stored in the steering wheel together with the inflator and is inflated and deployed between the steering wheel and the occupant of the driver's seat by gas supplied from the inflator, It is characterized in that The airbag cushion has: A steering side panel, which is located on the steering wheel side; a passenger side panel located on the passenger side and having a larger area than the steering side panel; a side panel connecting the steering side panel and the passenger side panel to form a side of the airbag cushion, The passenger side panel comprises: a recessed portion recessed toward the steering wheel side; an annular bulging portion, which is located around the recessed portion and bulges toward the passenger side, The predetermined portion of the passenger side panel is pulled toward the steering side by a predetermined means, thereby forming a central area closest to the steering wheel in the recessed portion, and a first inclined area gradually extending from the central area toward the passenger side, and forming a second inclined area connected to the first inclined area and gradually extending toward the passenger side in the bulging portion. The head of the occupant is restrained by the central area and the first and second inclined areas. The prescribed means include: a pair of main tethers located inside the airbag cushion, spanned between the steering side panel and the passenger side panel, and having a size that is tensioned when the airbag cushion is inflated and deployed to pull the passenger side panel toward the steering side; a pair of secondary tethers located inside the airbag cushion, spanned between the middle portions of the pair of main tethers and the passenger side panel, and having a size that is tensioned when the airbag cushion is inflated and deployed to pull the passenger side panel to the middle portion side of the pair of main tethers, The pair of main tethers are separated from each other and respectively connected to the edges of the recessed portion in the passenger side panel. The pair of auxiliary tethers are separated from each other and respectively connected to positions on the inner side of the edge of the recessed portion in the passenger side panel. A dimension from a middle portion of the pair of main tethers to the passenger side panel is longer than a dimension of the pair of secondary tethers.

2. The driver's seat airbag device according to claim 1, It is characterized in that The central area of ​​the recessed portion is located on the rotation axis of the steering wheel.

3. The driver's seat airbag device according to claim 1, characterized in that: When the recessed portion is viewed from the passenger side toward the steering wheel side, the recessed portion has a shape that is symmetrical in both vertical and horizontal directions.

4. The driver's seat airbag device according to claim 3, characterized in that: When the recessed portion is viewed from the passenger side toward the steering wheel side, the recessed portion has a shape in which a dimension in the up-down direction and a dimension in the left-right direction are the same.

5. The driver's seat airbag device according to claim 3, characterized in that: When the recessed portion is viewed from the passenger side toward the steering wheel side, the recessed portion has a shape in which a dimension in a vertical direction is longer than a dimension in a horizontal direction.

6. The driver's seat airbag device according to claim 3, characterized in that: When the recessed portion is viewed from the passenger side toward the steering wheel side, the recessed portion has a shape in which a dimension in a vertical direction is shorter than a dimension in a horizontal direction.

7. The driver's seat airbag device according to any one of claims 1 to 6, characterized in that: A vertical line perpendicularly intersecting the first inclined region and the second inclined region of the passenger side panel of the airbag cushion intersects the side panel.

8. The driver's seat airbag device according to claim 1, wherein: The width of the pair of main ties is wider than the width of the pair of secondary ties.

9. The driver's seat airbag device according to claim 1 or 8, characterized in that: The pair of main tethers and the pair of auxiliary tethers are arranged side by side in a vehicle width direction or a vehicle up-down direction.

10. The driver's seat airbag device according to any one of claims 1 to 6, characterized in that: The first inclined region and the second inclined region are inclined at an angle of 10° or more with respect to a reference plane orthogonal to the rotation axis of the steering wheel.

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