Airbag device for vehicles

Abstract

[Problem] To provide an airbag device for vehicles that is capable of improving occupant restraining force. [Solution] An airbag cushion 108 has a main chamber 120 and lobed chambers 130, 132. A panel member of the airbag cushion 108 includes: a main panel 134 that forms the upper surface, the lower surface, the front surface, and the rear surface of the main chamber 120; side panels 152, 154 that form the lateral surface of the main chamber 120 and the outer surface of the lobed chamber 130; and lobe panels 160, 162 that form the inner surfaces of the lobed chambers 130, 132. The lobe panel 160 includes: an outer peripheral part 160a that is joined with the side panel 152; a recessed edge part 160b that is formed such that a part of the outer periphery is cut out; and a pair of projecting areas 200, 202 that are formed in a tapered shape at both end parts of the recessed edge part 160b and have tip parts where the recessed edge part 160b and the outer peripheral part 160a are connected.

Description

Vehicle airbag device

[0001] The present invention relates to a vehicle airbag device that includes an airbag cushion that inflates and deploys between an instrument panel of a vehicle and an occupant seated in a front seat.

[0002] Airbag systems are now standard equipment on most modern vehicles. Airbag systems are safety devices that activate in emergencies such as vehicle collisions, and protect occupants by using an airbag cushion that inflates and deploys using gas force. There are various types of airbag systems depending on their installation location and purpose. For example, in the driver's seat, a front airbag is installed in the center of the steering wheel. In the passenger seat, a passenger airbag is installed in the instrument panel or its surrounding area.

[0003] The airbag cushions of various airbag devices are designed to fully restrain the occupant depending on the type of vehicle collision. For example, an airbag 24 shown in Figures 1 and 2 of Patent Document 1 is for a passenger seat, and has a center bag portion 28 added to the side of a main bag 26 to protect against a so-called oblique collision, which is an oblique collision of the vehicle.

[0004] JP 2018-24341 A

[0005] The center bag portion 28 of Patent Document 1 is a small-capacity inflatable portion added to the main bag 26. In recent years, there has been a demand for an improved occupant restraint force even for the added inflatable portion.

[0006] SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a vehicle airbag device that can improve the occupant restraint force.

[0007] In order to solve the above problems, a representative configuration of a vehicle airbag device according to the present invention is a vehicle airbag device including an inflator provided inside an instrument panel of a vehicle, and an airbag cushion formed into a bag shape by a plurality of panel members and inflated and deployed by gas from the inflator, wherein the airbag cushion has a main chamber that inflates and deploys between the instrument panel and an occupant seated in a normal posture in a front seat of the vehicle, and a pair of lobe chambers that inflates and deploys in a shape that protrudes rearward from both sides of the rear surface of the main chamber in the vehicle width direction, and the plurality of panel members are The device comprises a main panel that forms the upper, lower, front, and rear surfaces, a pair of side panels that form the sides of the main chamber and the outer surfaces of the lobe chamber, and a pair of lobe panels that form the inner surfaces of the lobe chamber, each of the pair of lobe panels having an outer periphery that forms the outer periphery of the lobe panel and is joined to the side panel, a recessed side portion that is formed by cutting out a part of the outer periphery and is joined to the main panel, and at least one protruding area that is formed in a tapered shape at the end portion of the recessed side portion of the lobe panel, and where the tip portion of the tapered shape connects the recessed side portion and the outer periphery.

[0008] According to the above feature, when the airbag cushion inflates and deploys, the protruding region of the lobe panel is pulled by the main panel and the side panel, generating tension in the lobe panel, which makes the lobe chamber less likely to collapse and allows it to maintain an independent posture. Therefore, with the above configuration, the occupant restraint force of the lobe chamber is increased, making it possible to appropriately restrain the occupant's head, etc.

[0009] The protruding regions may be provided at both ends of the recessed side portion. With this configuration, the protruding regions at both ends of the recessed side portion are pulled by the main panel and the side panel, and tension is efficiently generated in the lobe panel, thereby making it possible to keep the lobe panel in a taut state.

[0010] The above-mentioned side panel may have a tuck-in portion provided in a predetermined range of the portion forming the outer surface of the lobe chamber, and the tuck-in portion may be formed by folding back along a crease extending in the vertical direction, and the side panel may be joined to the lobe panel with the tuck-in portion formed.

[0011] In the above configuration, the portion of the side panel that forms the outer surface of the lobe chamber is joined to the lobe panel in a partially folded state by the tuck-in portion, and has a larger area than the lobe panel when unfolded. That is, the lobe panel has a smaller area than the panel member on the outer side of the lobe chamber, making it easier to tension. With this configuration, tensioning the lobe panel can maintain the independent posture of the lobe chamber and improve occupant restraint force.

[0012] Furthermore, because the lobe panels are smaller and more easily tensioned than the lobe portions of the side panels, the lobe chambers are pulled by the lobe panels and tend to tilt toward the center of the main chamber. This allows the pair of lobe chambers to deform so that the space between them narrows. This allows the airbag cushion to hold in and restrain the intruding occupant, improving occupant restraint performance.

[0013] The above-mentioned side panel may have a tuck-in portion provided in a predetermined range of the portion forming the outer surface of the lobe chamber, and the tuck-in portion may be formed by folding back at a crease extending in a direction intersecting the direction in which the lobe chamber protrudes when inflated and deployed, and the side panel may be joined to the lobe panel with the tuck-in portion formed.

[0014] Even with the above-described configuration, the portion of the side panel that forms the outer surface of the lobe chamber is joined to the lobe panel in a partially folded state by the tuck-in portion, and has a larger area than the lobe panel when unfolded. That is, the lobe panel has a smaller area than the panel member on the outer side of the lobe chamber, making it easier to tension. Even with this configuration, tensioning the lobe panel can maintain the independent posture of the lobe chamber and improve occupant restraint force.

[0015] The protruding region may be interposed between the main panel and the side panel on the surface of the airbag cushion.

[0016] According to the above configuration, the protruding region of the lobe panel is easily pulled by the main panel and the side panel, so that tension can be efficiently applied to the lobe panel to make it taut.

[0017] The airbag cushion may further have a Y-shaped joint on the surface of the airbag cushion, which is formed in a Y shape along a line extending from the edge of the protruding region and the tip of the protruding region, and which joins the protruding region to the main panel and the side panel.

[0018] With the above configuration, the protruding area of ​​the lobe panel is easily pulled by the main panel and the side panel, so that tension can be efficiently applied to the lobe panel to make it taut.

[0019] The recessed side portion may extend in a direction that opens outward at both ends. With this configuration, when the protruding regions provided on both ends of the recessed side portion are pulled by the main panel and the side panel, tension is applied to the lobe panel in a direction that opens the recessed side portion outward. This makes it possible to efficiently apply tension to the entire lobe panel.

[0020] According to the present invention, it is possible to provide a vehicle airbag device that can improve the occupant restraint force.

[0021] 1(b) is a diagram illustrating an overview of a vehicle airbag device according to an embodiment of the present invention; FIG. 1(b) is a schematic cross-sectional view taken along line A-A of the airbag cushion of FIG. 1(b); FIG. 1(b) is a diagram illustrating the airbag cushion alone when inflated and deployed; FIG. 3 is a diagram illustrating each panel member forming the airbag cushion of FIG. 3; FIG. 4 is a diagram illustrating an airbag cushion formed by each panel of FIG. 4; FIG. 5(a) is a diagram illustrating the lobe panel of FIG. 5(a) from various directions; FIG. 4(b) is a diagram illustrating a process of forming a lobe chamber from the side panels; FIG. 3(b) is a diagram illustrating a process of the airbag cushion of FIG. 3(b) restraining an occupant; FIG. 2 is a diagram illustrating a state in which the airbag cushion of FIG. 2 restrains an occupant.

[0022] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Dimensions, materials, and other specific values ​​shown in the embodiments are merely examples for facilitating understanding of the invention and, unless otherwise specified, do not limit the present invention. In this specification and drawings, elements having substantially the same functions and configurations are designated by the same reference numerals to avoid redundant explanation, and elements not directly related to the present invention are not shown.

[0023] 1A and 1B are diagrams illustrating an example of an outline of a vehicle airbag device 100 according to an embodiment of the present invention. Fig. 1A is a diagram illustrating the vehicle airbag device 100 before it is deployed. In this embodiment, the vehicle airbag device 100 is installed in front of a front-row right seat 104 as a passenger airbag for a front passenger seat in a left-hand drive vehicle.

[0024] In this embodiment, the direction in which a vehicle normally travels is referred to as "forward" or "forward." The direction opposite to the direction in which a vehicle normally travels is referred to as "rear" or "backward." When these two directions are expressed in terms of coordinates, they are referred to as "forward-rear directions." Furthermore, a direction perpendicular to the forward-rear directions, in which a passenger is seated in a normal posture facing forward, the direction of the right hand is referred to as "right" or "rightward direction," and the direction of the left hand is referred to as "left" or "leftward direction." When these two directions are expressed in terms of coordinates, they are referred to as "left-right directions."

[0025] 1(a) and other drawings, the fore-and-aft direction of the vehicle is indicated by arrows F (Forward) and B (Back), the left-right direction, which is also the vehicle width direction, is indicated by arrows L (Left) and R (Right), and the up-down direction of the vehicle is indicated by arrows U (Up) and D (Down). In particular, "up" refers to the direction of the head of an occupant sitting in a normal position in the seat, and "down" refers to the direction of the lower legs of the occupant.

[0026] An airbag cushion 108 (see FIG. 1B) of the vehicle airbag device 100 is stored in a storage section 106 provided in an instrument panel 102. The storage section 106 is installed in front of a seat 104 in the vehicle. The storage section 106 also stores an inflator 110 (see FIG. 2) which is a gas generator, together with the airbag cushion 108.

[0027] Fig. 1(b) is a diagram illustrating the state of the vehicle airbag device 100 of Fig. 1(a) after it has been activated. When a collision is predicted or detected, the airbag cushion 108 inflates and deploys from the storage portion 106 (see Fig. 1(a)) toward the front of the seat 104. The airbag cushion 108 is formed into a bag shape by overlapping and sewing or bonding a plurality of panel members that form the surface of the airbag cushion 108.

[0028] Figure 2 is a schematic cross-sectional view of the airbag cushion 108 taken along line AA in Figure 1(b) , and also illustrates an occupant 112 seated in the seat 104 in a normal position.

[0029] 2 is an example of a dummy used in automobile crash tests. Examples of dummies that can be used for the occupant 112 include the AM50 and AF05 Hybrid III dummies, which are used for frontal crash tests.

[0030] AM50 is a dummy that simulates a male with a height of approximately 175 cm, a seated height of approximately 88.4 cm, and a weight of approximately 78 kg, which corresponds to 50% of the average American adult male. AF05 is a dummy that simulates a female with a small build, with a height of approximately 145 cm, a seated height of approximately 79 cm, and a weight of approximately 45 kg. Each of these dummies was created based on the standards of the National Highway Traffic Safety Administration (NHTSA).

[0031] A dummy that can be used for the occupant 112 is the THOR dummy (Test Device for Human Occupant Restraint) for frontal collisions. The THOR dummy is an anthropomorphic dummy developed as a successor to the Hybrid III dummy, and is modeled only on a male of average build. THOR dummies include the ATD-THOR50M (US) specification model and the ATD-THOR50M (EU) specification model, both of which are finite element (FE) models based on NHTSA standards for THOR 50% adult male crash safety performance tests. These THOR-50M dummies are specified to have a seated height of approximately 90.65 cm and a weight of approximately 76.6 kg.

[0032] The airbag cushion 108 inflates and deploys between the instrument panel 102 and an occupant 112 seated in a normal position in the seat 104 (see FIG. 1B). In particular, the airbag cushion 108 of this embodiment inflates and deploys between the upper surface 102a and the windshield 114, and between the rear surface 102b and the occupant 112 in the seat 104, while remaining in contact with the upper surface 102a and the rear surface 102b of the instrument panel 102 and standing independently, thereby being able to restrain the occupant 112 from the front of the vehicle.

[0033] The airbag cushion 108 is connected to an inflator 110, which is a gas generator, by an inflator connector 118. The inflator 110 is fixed to the inside of the top surface 102a of the instrument panel 102 using stud bolts (not shown), and the portion of the inflator 110 having gas ejection holes is inserted into the airbag cushion 108 through the inflator connector 118.

[0034] The inflator 110 is activated by a signal sent from the vehicle side and supplies gas to the inside of the airbag cushion 108. The airbag cushion 108 begins to inflate with the gas from the inflator 110, and the force of the expansion presses against the cover of the storage section 106, causing it to tear open, and the airbag cushion 108 inflates and deploys toward the seat 104 (see FIG. 1(b)).

[0035] In this embodiment, a disk-shaped inflator 110 is used. Currently popular inflators include types that are filled with gas generating agent and burn it to generate gas, types that are filled with compressed gas and supply gas without generating heat, and hybrid types that use both combustion gas and compressed gas. Any of these types can be used as the inflator 110.

[0036] The diffuser 116 is a member that rectifies the flow of gas supplied from the inflator 110. The diffuser 116 is disposed around the inflator connection portion 118 on the inside of the airbag cushion 108, and covers the inflator 110 inserted into the airbag cushion 108.

[0037] The diffuser 116 has a rear opening 116b as an opening for the gas to flow through. The diffuser 116 guides the gas in the front-rear direction through these openings, thereby enabling the airbag cushion 108 to be efficiently filled with gas.

[0038] 3A and 3B are diagrams illustrating the airbag cushion 108 alone when inflated and deployed in Fig. 1B. Fig. 3A is a diagram illustrating the airbag cushion 108 in Fig. 1B as viewed from the left side in the vehicle width direction.

[0039] The airbag cushion 108 is provided with an inflator connection portion 118 as a portion into which a portion of the inflator 110 (see FIG. 2) is inserted. The inflator connection portion 118 is provided at a portion of the airbag cushion 108 that overlaps the instrument panel 102 from above, and in this embodiment, is provided at a portion forward of the center of the airbag cushion 108.

[0040] The inflation portion of the airbag cushion 108 is provided with a main chamber 120 as a major compartment. The main chamber 120 is the portion of the inflation portion that is larger in vertical dimension than the inflator connection portion 118 and is formed rearward of the vehicle. The main chamber inflates and deploys between the instrument panel (see FIG. 2) and an occupant 112 seated in the correct posture in the seat, and widely restrains the occupant from the front of the vehicle.

[0041] 2, the main chamber 120 is inflated so that its upper end 120a is located near the windshield 114 and its lower end 120b is located below an imaginary line L1 extending rearward from the upper surface 102a of the instrument panel 102. This enables the main chamber 120 to widely restrain the upper body of the occupant 112, mainly from the head 172 to the chest 184.

[0042] The airbag cushion 108 is provided with a front contact portion 122 as an inflatable portion for maintaining the airbag cushion 108 in an upstanding position. The front contact portion 122 inflates from the inflator connecting portion 118 along the upper surface 102a of the instrument panel 102 so as to protrude in a wedge shape toward the front of the vehicle. The front contact portion 122 fits into the space between the instrument panel 102 and the windshield 114 and makes surface contact with the upper surface 102a of the instrument panel 102, thereby supporting the airbag cushion 108 in an upstanding position.

[0043] The main chamber 120 is also provided with a rear contact portion 124 as a portion that supports the self-standing posture of the airbag cushion 108. The rear contact portion 124 is provided in the main chamber 120 on the front side of an area that is below an imaginary line L1 (see FIG. 2 ) that extends from the top surface 102a of the instrument panel 102, so as to come into contact with the rear surface 102b of the instrument panel 102.

[0044] The airbag cushion 108 has a front contact portion 122 that contacts the upper surface 102a of the instrument panel 102, and a main chamber 120 that contacts the portion of the rear surface 102b of the instrument panel 102 that extends in the vertical direction via a rear contact portion 124, making it possible to use the upper surface 102a and the rear surface 102b as reaction surfaces when restraining an occupant.

[0045] The diffuser 116 in Fig. 2 also helps to maintain the self-standing posture of the airbag cushion 108. More specifically, the rear opening 116b of the diffuser 116 is open toward the main chamber 120 at the rear of the vehicle, and quickly guides the gas supplied from the inflator 110 to the main chamber 120. Therefore, the rear contact portion 124 of the main chamber 120 quickly inflates and deploys, allowing the airbag cushion 108 to quickly become self-standing.

[0046] The cushion upper surface portion 126 in Figure 3(a) is the portion that forms the upper surface of the airbag cushion 108, extending from the front contact portion 122 to the main chamber 120. The cushion upper surface portion 126 may contact the windshield 114 (Figure 2), or may be inflated and deployed away from the windshield 114. As described above, the airbag cushion 108 can maintain an independent posture without contacting the windshield 114 by utilizing the front contact portion 122 and the rear contact portion 124. A configuration in which the cushion upper surface portion 126 is inflated and deployed away from the windshield 114 can reduce the strain that may be placed on the windshield 114.

[0047] 3B is a top view of the airbag cushion 108 of FIG. 3A. The airbag cushion 108 has a pair of lobe chambers 130, 132 on either side of the rear cushion portion 128, which are characteristically shaped portions of the airbag cushion 108.

[0048] A cushion rear surface portion 128, which is the rear surface of the main chamber 120, is formed across the vertical direction in an area of ​​the main chamber 120 that faces the vehicle rear side occupant 112 (see FIG. 2). The cushion rear surface portion 128 restrains the area from the head 172 to the chest 184 and abdomen 190 of the occupant 112 from the front of the vehicle.

[0049] The pair of lobe chambers 130, 132 are provided on both sides in the vehicle width direction at the upper part of the cushion rear surface portion 128, and inflate to protrude rearward of the vehicle. The lobe chambers 130, 132 mainly restrain the temples 174 of the occupant 112 (see FIG. 8(b)).

[0050] FIG. 4 illustrates the panel members that form the airbag cushion 108 of FIG.

[0051] FIG. 4A is a diagram illustrating the main panel 134 of the airbag cushion 108 of FIG. 3B laid out on a flat surface.

[0052] The main panel 134 is a portion of the airbag cushion 108 that mainly forms the surfaces other than the side surfaces of the main chamber 120. In more detail, the main panel 134 forms the cushion upper surface portion 126, the cushion rear surface portion 128, and the front and lower surfaces of the airbag cushion 108 that extend from the main chamber 120 to the front contact portion 122 in FIG.

[0053] The main panel 134 is in the form of a long strip, and is used by joining side edges 136, 138 to the edges of side panels 152, 154 shown in Figures 4(b) and 4(c) by sewing or the like. Ends 140, 142 of the main panel 134 are joined to each other by sewing or the like.

[0054] Concave and concave curved portions 144, 146 are formed on portions of the side edges 136, 138 of the main panel 134. Concave side portions 160b, 162b of lobe panels 160, 162 (see FIGS. 4(d) and 4(e)) that form the insides of the lobe chambers 130, 132 (see FIG. 3(b)) are joined to the curved portions 144, 146, respectively.

[0055] The main panel 134 is provided with an inflator connection portion 118 into which the inflator 110 (see FIG. 2) is inserted. The inflator connection portion 118 is formed at a location of the main panel 134 that overlaps the upper surface 102a of the instrument panel 102 from above.

[0056] The inflator connecting portion 118 includes an opening 148, a bolt hole 150, and the like. A portion of the inflator 110 (see FIG. 2 ) having a gas ejection hole is inserted into the opening 148. A stud bolt extending from a retainer ring (not shown) attached to the inflator 110 is inserted into the bolt hole 150. The airbag cushion 108 is fixed inside the storage portion 106 by connecting the inflator connecting portion 118 to the inflator 110.

[0057] Fig. 4(b) is a diagram illustrating the left side panel 152 in the vehicle width direction of Fig. 3(b) when unfolded and laid flat. The side panel 152 is a pair of panel members that form the left and right side surfaces in the vehicle width direction of the airbag cushion 108. The side panel 152, together with the right side panel in the vehicle width direction (see Fig. 4(c)), is provided in a shape that is symmetrical on the left and right sides in the vehicle width direction of the airbag cushion 108 (see Fig. 3(b)).

[0058] The side panel 152 forms the outer surface in the vehicle width direction, covering the main chamber 120, the front contact portion 122, and the lobe chamber 130 in Figure 3(a) . The side panel 152 is also provided with a vent hole 153 for discharging gas.

[0059] Fig. 4(c) is a diagram illustrating the side panel 154 on the right side in the vehicle width direction of Fig. 3(b) when it is unfolded and laid flat. The side panel 154 has a shape symmetrical to the side panel 152 in Fig. 4(b) and has a similar configuration to the side panel 152.

[0060] 4(d) is a diagram illustrating the lobe panel 160 on the left side in the vehicle width direction of FIG. 3(b) laid out on a flat surface. The lobe panel 160 is a panel member that forms the inner surface in the vehicle width direction of the lobe chamber 130. The lobe panel 160 has a shape that is close to a semicircle, with an outer periphery 160a joined to the side panel 152 and a recessed edge 160b joined to the main panel 134.

[0061] Fig. 4(e) is a diagram illustrating the lobe panel 162 on the right side in the vehicle width direction of Fig. 3(b) laid out on a flat surface. The lobe panel 162 has a shape symmetrical to the lobe panel 160 in Fig. 4(d) and has a similar configuration to the lobe panel 162.

[0062] Figure 5 is a diagram illustrating an airbag cushion 108 formed by the panels of Figure 4. Figure 5(a) is a diagram illustrating the airbag cushion 108 as viewed from above.

[0063] The main panel 134 is disposed around the top, bottom, front and rear surfaces of the main chamber 120 of the airbag cushion 108. For example, the main panel 134 forms the cushion upper surface portion 126 and the cushion rear surface portion 128.

[0064] The side panels 152 , 154 are joined to the side edges 136 , 138 of the main panel 134 and form the sides of the main chamber 120 and the sides of the lobe chamber 130 .

[0065] The lobe panels 160, 162 are joined to the side edges 136, 138 of the main panel 134 and the edges of the side panels 152, 154, and form the transversely inward surfaces of the lobe chambers 130, 132. In particular, the lobe panels 160, 162 are joined to the edges of the outer lobe panel portions 164, 165 of the side panels 152, 154, which form the lobe chamber 130.

[0066] FIG. 5B is a perspective view illustrating the airbag cushion 108 of FIG. 5A as viewed from the rear lower left.

[0067] The lobe chambers 130 inflate and deploy so as to protrude rearward from the cushion rear surface portion 128. At this time, in this embodiment, tension is applied to the lobe panels 160, 162, thereby maintaining the protruding shape of the lobe chambers 130, 132.

[0068] 4(d), the lobe panels 160 and 162 are symmetrical in shape, and the shape and function of the lobe panel 160 are also applied to the lobe panel 162.

[0069] As described above, the lobe panel 160 has a shape that approximates a semicircle. The outer periphery 160a of the lobe panel 160 is the edge that forms the outer periphery of the lobe panel 160 and is joined to the edge of the outer lobe panel portion 164 of the side panel 152.

[0070] The recessed side portion 160b is a recessed edge formed by cutting out a portion of the outer periphery of the lobe panel 160. The recessed side portion 160b is joined to the side edge 136 (see FIG. 4A) of the main panel 134, particularly near the curved portion 144.

[0071] The lobe panel 160 has at least one protruding region 200 or one protruding region 202. In this embodiment, a pair of protruding regions 200, 202 is provided at each end of the recessed side portion 160b of the lobe panel 160. The protruding regions 200, 202 are formed to protrude in a tapered shape, and the ends of the tapered shape connect the ends of the recessed side portion 160b to the outer periphery 160a. The protruding regions 200, 202 are joined so as to be positioned between the main panel 134 and the side panel 152, and are used to obtain tension from the main panel 134 and the side panel 152.

[0072] 6A and 6B are diagrams illustrating the lobe panel 160 of FIG. 5A from various directions. FIG. 6A is an enlarged view of the vicinity of the protruding region 200 of the lobe panel 160 of FIG. 5A. The shape and function of the protruding region 200 described below also apply to the protruding region 202.

[0073] The protruding region 200 is disposed on the surface of the airbag cushion 108 so as to be inserted between the main panel 134 and the side panel 152. For example, the edge 200a of the protruding region 200 corresponds to the end of the recessed side portion 160b and is joined to the side edge 136 of the main panel 134. The edge 200b of the protruding region 200 corresponds to the end of the outer periphery 160a and is joined to the edge of the side panel 152.

[0074] With the above configuration, the protruding regions 200, 202 are easily pulled by both the panel members of the main panel 134 and the side panel 152 when the airbag cushion 108 is inflated and deployed. Therefore, when the airbag cushion 108 is inflated and deployed, the lobe panel 160 receives tension from the main panel 134 and the side panel 152 via the protruding regions 200, 202, and can become taut.

[0075] A Y-shaped joint 210 is formed on the surface of the airbag cushion 108 as a joint between three panel members. The Y-shaped joint 210 is formed in a Y shape by the joint between the edge 200a of the protruding region 200 and the main panel 134, the joint between the edge 200b of the protruding region 200 and the side panel 152, and the joint between the main panel 134 and the side panel 152 along a line extending from the tip of the protruding region 200.

[0076] The formation of the Y-shaped joints 210 also makes it easier for the protruding region 200 to be pulled by the main panel 134 and the side panel 152. Joints similar to the Y-shaped joints 210 are also formed around the periphery of the protruding region 202 (see FIG. 5(b)). These Y-shaped joints 210 also make it possible to efficiently apply tension to the lobe panel 160 via the protruding regions 200, 202, thereby tensioning it.

[0077] FIG. 6B is a diagram illustrating the lobe panel 160 of FIG. 5A as viewed from the center side of the airbag cushion 108 in the vehicle width direction.

[0078] When the airbag cushion 108 (see FIG. 5A) is inflated and deployed, the lobe panel 160 is placed in a tensile state due to a force 212 exerted by the lobe chamber 130 as it tries to expand, and tension forces 214, 216 exerted when the protruding areas 200, 202 are pulled by the main panel 134 (see FIG. 6A) and the side panel 152.

[0079] The lobe chambers 130, 132 in Figure 5(b) are less likely to collapse outward because the inner lobe panels 160, 162 are in a tensed state. That is, the lobe chambers 130, 132 can maintain their independent posture and are less likely to open apart. Therefore, the lobe chambers 130, 132 can suitably restrain the occupant's head by wrapping it from both sides, thereby improving the occupant restraint force of the airbag cushion 108.

[0080] The recessed side portion 160b in Figure 6(b) extends in a direction in which both ends open outward. With this configuration, when the protruding regions 200, 202 on both ends of the recessed side portion 160b are pulled by the main panel 134 (see Figure 6(a)) and the side panel 152, tension forces 214, 216 are applied to the lobe panel 160 in a direction in which the recessed side portion 160b opens outward. Therefore, when the airbag cushion 108 is inflated and deployed, tension can be efficiently applied to the entire lobe panel 160, thereby tensioning it.

[0081] 7A and 7B are diagrams illustrating a process of forming the lobe chamber 130 (see FIG. 3B) from the side panel 152 of FIG. 4B. FIG. 7A is a diagram illustrating the side panel 152 in an unfolded state placed on a flat surface.

[0082] The main chamber side surface portion 156 is a portion of the side panel 152 that forms the side surface of the main chamber 120 (see FIG. 5A). The outer lobe panel portion 164 is a portion of the side panel 152 that forms the outer side of the lobe chamber 130 in the vehicle width direction.

[0083] The outer lobe panel portion 164 has its outer periphery 158 joined to the outer periphery 160a of the lobe panel 160 of FIG. 4(d), and together with the lobe panel 160 forms the lobe chamber 130 (see FIG. 5(a)).

[0084] The side panel 152 has a tuck-in portion 220 in the outer lobe panel portion 164. The tuck-in portion 220 is a region that is folded over when joined to the lobe panel 160. The tuck-in portion 220 is formed by folding back an area of ​​the outer lobe panel portion 164 near the main chamber side portion 156 along a crease that extends in the vertical direction. The crease that extends in the vertical direction extends in a direction that intersects with the direction in which the lobe chamber 130 (see FIG. 5( a)) protrudes when inflated and deployed.

[0085] Figure 7(b) shows the side panel 152 of Figure 7(a) after the tuck-in portion 220 has been formed. By folding the tuck-in portion 220, the outer periphery 158 of the outer lobe panel portion 164 assumes approximately the same shape and length as the outer periphery 160a of the lobe panel 160 (see Figure 6(b)). In this state, the outer periphery 158 of the outer lobe panel portion 164 and the outer periphery 160a of the lobe panel 160 are joined together to form the lobe chamber 130 (see Figure 5(a)).

[0086] Figure 7(c) is a cross-sectional view taken along line B-B of side panel 152 in Figure 7(b). Tuck-in portion 220 is formed by folding back a portion of outer lobe panel portion 164. In this case, outer lobe panel portion 164 is designed so that its area when expanded with tuck-in portion 220 removed is larger than that of lobe panel 160 (see Figure 6(b)). By forming tuck-in portion 220, outer lobe panel portion 164 becomes approximately the same size as lobe panel 160.

[0087] The lobe chamber 130 (see FIG. 5(a)) is configured such that when gas flows in, the tuck-in portion 220 unfolds, causing the outer lobe panel portion 164 to expand more. In other words, the lobe panel 160 has a smaller area than the outer lobe panel portion 164 and is configured to be more easily subjected to tension. Therefore, the inflated lobe chamber 130 can maintain an independent posture due to the inner lobe panel 160 being more tense, thereby improving the occupant restraint force.

[0088] Furthermore, because the lobe panel 160 (see FIG. 6(b)) is smaller and more easily tensioned than the outer lobe panel 164 of the side panel 152, the lobe chambers 130, 132 are pulled by the lobe panels 160, 162 and tend to tilt toward the center of the main chamber 120, as illustrated in FIG. 8(a) described below. In other words, the pair of lobe chambers 130, 132 are able to deform so that the space between them narrows. This allows the airbag cushion 108 to hold and restrain the intruding occupant 112, improving the occupant 112 restraint performance.

[0089] 8A and 8B are diagrams illustrating the process in which the airbag cushion 108 of Fig. 3B restrains the occupant 112. Fig. 8A is a diagram illustrating the state immediately after the airbag cushion 108 is inflated and deployed.

[0090] The airbag cushion 108 inflates and deploys in front of the vehicle occupant 112 seated in the seat 104 (see FIG. 1B). At this time, the airbag cushion 108 not only inflates such that the cushion rear surface 128 of the main chamber 120 is inflated in front of the occupant 112, but also such that the lobe chambers 130, 132 protrude rearward from both sides of the cushion rear surface 128 in the vehicle width direction.

[0091] 8(b) is a diagram showing the state in which the occupant 112 of FIG. 8(a) has entered the airbag cushion 108. In an oblique collision, which is a collision from the diagonal front, the occupant 112 may also move diagonally forward. In this case, the lobe chambers 130, 132 function effectively to protect the occupant 112.

[0092] As illustrated in Figure 8(b), for example, when an occupant 112 moves diagonally forward to the left, the airbag cushion 108 restrains the head 172 of the occupant 112 from the front of the vehicle with the cushion rear portion 128, and also restrains the head 172 of the occupant 112 from the side of the head 174 with the lobe chamber 130.

[0093] In an oblique collision or the like, when the head 172 of the occupant 112 approaching diagonally forward comes into contact only with the rear cushion portion 128, a clockwise rotational force (rotation 176 shown by the arrow) around the neck as viewed from above may be generated in the head 172. It has been found that such rotation 176 of the head 172 is likely to increase the injury level of the occupant 112.

[0094] In this embodiment, the cushion rear surface portion 128 and the lobe chamber 130 actively restrain the area from the front of the head 172 to the sides 174, making it possible to reduce or counteract and absorb the rotation 176 that occurs in the head 172. With this configuration, in various collision types including an oblique collision, the angular velocity of the rotation 176 of the head 172 of the occupant 112 can be reduced, and the injury level to the head 172 associated with the rotation 176 can be suppressed.

[0095] As described with reference to FIG. 6(b), the lobe panels 160, 162 can be pulled by the main panel 134 and the side panel 152 to obtain tension by utilizing the concave side portions 160b, 162b (see FIGS. 4(d) and 4(e)) and the protruding regions 200, 202, 224, 226. In addition, as described with reference to FIG. 7(c), the lobe panels 160, 162 are configured to have smaller areas than the outer lobe panel portions 164, 165. This allows the lobe panels 160, 162 to be subjected to greater tension and tension than the outer lobe panel portions 164, 165.

[0096] With the above configuration, the lobe chambers 130, 132 in Figure 8(b) tend to generate inward forces 180, 182 as they are pulled by the lobe panels 160, 162, respectively, making it possible to restrain the head 172 of the occupant 112 by wrapping it around from both sides. In addition to this effect, the lobe chambers 130, 132 are ensured to have a large volume by the three-dimensionally shaped outer lobe panel portion 164 (see Figure 7(c)) and the similar outer lobe panel 165. These enable the lobe chambers 130, 132 to exert a high occupant restraint force on the head 172 of the occupant 112.

[0097] 2 restrains the occupant 112. When the occupant 112 enters the cushion rear portion 128, a force 186 may be generated in the airbag cushion 108, in which the rear contact portion 124 of the main chamber 120 pushes the rear surface 102b of the instrument panel 102 forward, and a force 188 may be generated in which the front contact portion 122 pushes the upper surface 102a of the instrument panel 102 downward.

[0098] More specifically, when the occupant 112 falls forward, a force 186 is generated in the main chamber 120 that rotates it downward around the inflator connection portion 118, causing the rear contact portion 124 to interfere with the rear surface 102b of the instrument panel 102. Furthermore, when the occupant 112 generates a force in a direction that lifts the main chamber 120, a force 188 is generated in the front contact portion 122 that rotates it downward around the inflator connection portion 118, causing the front contact portion 122 to interfere with the upper surface 102a of the instrument panel 102.

[0099] Due to the above-described action, the airbag cushion 108 contacts the top surface 102a and the rear surface 102b of the instrument panel 102, and by using the top surface 102a and the rear surface 102b as reaction surfaces, the airbag cushion 108 can restrain the occupant 112 in a stable position. In this way, the airbag cushion 108 can maintain an upright position by making full use of the instrument panel 102.

[0100] 8(b), the airbag cushion 108 generates inward forces 180, 182 in the lobe chambers 130, 132 by utilizing the shape of the lobe panels 160, 162 and the difference in area between the lobe panels 160, 162 and the outer lobe panel portions 164, 165. Due to these actions, the airbag cushion 108 utilizes the lobe chambers 130, 132 to preferably restrain the head 172 of the occupant 112, thereby improving occupant restraint performance.

[0101] The airbag cushion 108 has a simpler configuration, uses less material, and is less costly than conventional methods that utilize the tension of an internal tether or the like to form a protrusion on the airbag cushion 108. Furthermore, by omitting the internal tether or the like, gas flows smoothly inside the airbag cushion 108, ensuring rapid inflation and deployment.

[0102] Furthermore, the airbag cushion 108 of this embodiment can maintain an independent posture by having the front contact portion 122 contact the upper surface 102a of the instrument panel 102 and the main chamber 120 contact the rear surface 102b of the instrument panel 102 via the rear contact portion 124. With this configuration, the airbag cushion 108 can stabilize its posture and efficiently restrain the occupant 112.

[0103] Furthermore, the airbag cushion 108 guides gas into the main chamber 120 via the diffuser 116, thereby quickly inflating and deploying the main chamber 120. This also allows the airbag cushion 108 to come into contact with the instrument panel 102, making it possible to stabilize the posture of the airbag cushion 108 more quickly.

[0104] Although preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the above-described embodiments are merely preferred examples of the present invention, and other embodiments may be implemented or performed in various ways. Unless otherwise specified in the present specification, the present invention is not limited to the detailed shapes, sizes, and configurations of parts shown in the accompanying drawings. Furthermore, the expressions and terms used in the present specification are for the purpose of explanation and are not intended to be limiting unless otherwise specified.

[0105] Therefore, it is clear that a person skilled in the art can think of various modifications or alterations within the scope of the claims, and it is understood that these also naturally fall within the technical scope of the present invention.

[0106] The present invention can be used in a vehicle airbag device that includes an airbag cushion that inflates and deploys between the instrument panel of the vehicle and an occupant seated in a front seat.

[0107] 100...vehicle airbag device, 102...instrument panel, 102a...upper surface, 102b...rear surface, 104...seat, 106...storage section, 108...airbag cushion, 110...inflator, 112...occupant, 114...windshield, 116...diffuser, 116b...rear opening, 118...inflator connection section, 120...main chamber, 120a...upper end, 120b...lower end, 122...front contact section, 124...rear contact section, 126...cushion upper surface section, 128...cushion rear surface section, 130, 132...lobe chamber, 134...main panel, 136, 138...side edges, 140, 142...ends, 144, 146... Curved portion, 148...opening, 150...bolt hole, 152...side panel, 153...vent hole, 154...side panel, 156, 157...main chamber side portion, 158...periphery, 160...lobe panel, 160a...periphery, 160b...concave side portion, 162...lobe panel, 164, 165...outer lobe panel portion, 172...head, 174...side of head, 176...rotation, 180...force, 184...chest, 186...force, 188...force, 190...abdomen, 200, 202, 224, 226...protruding area, 200a, 200b...edge, 210...Y-shaped joint, 212...force, 214, 216...tension, 220, 228...tuck-in portion, L1...imaginary line

Claims

1. A vehicle airbag device comprising: an inflator provided inside the instrument panel of a vehicle; and an airbag cushion formed into a bag shape by a plurality of panel members that inflates and deploys with gas from the inflator, wherein the airbag cushion has: a main chamber that inflates and deploys between the instrument panel and an occupant seated in a normal posture in a front seat of the vehicle; and a pair of lobe chambers that inflate and deploy in a shape that protrudes rearward from both sides of the rear surface of the main chamber in the vehicle width direction, wherein the plurality of panel members include: a main panel that forms the upper, lower, front, and rear surfaces of the main chamber; a pair of side panels that form the side surfaces of the main chamber and the outer surfaces of the lobe chamber; and a pair of lobe panels that form the inner surfaces of the lobe chamber, wherein each of the pair of lobe panels has: an outer periphery that forms the outer periphery of the lobe panel and is joined to the side panel; and a recessed side portion that is formed by cutting out a part of the outer periphery and is joined to the main panel. and at least one protruding region formed in a tapered shape at an end portion of the recessed side portion of the lobe panel, the protruding region having a tip end portion of the tapered shape connecting the recessed side portion and the outer periphery.

2. The vehicle airbag device according to claim 1, wherein the protruding regions are provided at both ends of the recessed side portion.

3. A vehicle airbag device as described in claim 1 or 2, characterized in that the side panel has a tuck-in portion provided in a predetermined range of the portion forming the outer surface of the lobe chamber, the tuck-in portion being formed by folding back along a crease extending in the vertical direction, and the side panel is joined to the lobe panel with the tuck-in portion formed.

4. A vehicle airbag device as described in claim 1 or 2, characterized in that the side panel has a tuck-in portion provided in a predetermined range of a portion that forms the outer surface of the lobe chamber, the tuck-in portion being formed by folding back at a crease that extends in a direction that intersects with the direction in which the lobe chamber protrudes when inflated and deployed, and the side panel is joined to the lobe panel with the tuck-in portion formed.

5. A vehicle airbag device as claimed in claim 1 or 2, characterized in that the protruding region is inserted between the main panel and the side panel on the surface of the airbag cushion.

6. The vehicle airbag device according to claim 1 or 2, wherein the airbag cushion further has a Y-shaped joint on the surface of the airbag cushion that is formed along the edge of the protruding region and a line segment extending from the tip of the protruding region, and where the protruding region is joined to the main panel and the side panel.

7. The vehicle airbag device according to claim 2, wherein both ends of the recessed side portion extend in a direction that opens outward.

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