Side airbag device and method for manufacturing same

Abstract

The present invention provides a side airbag device in which the deployment behavior of a sub-chamber can be improved by a simple method to further enhance occupant safety. A side airbag device 1 comprises an airbag 30 that deploys beside an occupant seated in a vehicle seat 3, and an inflator 33 that supplies a gas for deployment to the airbag 30. The airbag 30 has a main chamber 31 with the inflator 33 built-in, and a sub-chamber 32 that deploys closer to the occupant than the main chamber 31. The main chamber 31 and the sub-chamber 32 communicate via a communicating hole 51. The sub-chamber 32 has, in a flattened-out state, a vertical center 32O located above the center 51A of the communicating hole 51, and, in a stowed state, the portion 32A of the sub-chamber 32 that is above the communicating hole 51 in the flattened-out state is provided folded over toward the occupant side.

Description

Side airbag device and manufacturing method thereof

[0001] The present invention relates to a side airbag device and a method for manufacturing the same.

[0002] Side airbag devices are installed in vehicles to protect occupants seated in vehicle seats during a side collision. For example, the side airbag device disclosed in Patent Document 1 has an airbag that can inflate and deploy a main chamber and a sub-chamber with a single inflator. The sub-chamber is smaller than the main chamber and inflates and deploys more inward in the vehicle width direction than the main chamber.

[0003] Patent Publication No. 2012-179956

[0004] According to the side airbag device of Patent Document 1, the inflated main chamber and sub-chamber press against the occupant's shoulders to buttocks, reducing chest injury. However, if the sub-chamber inflates and deploys so that it overlaps with the occupant's arms, the sub-chamber may press the occupant's arms inward in the vehicle width direction, which may result in more pressure than necessary on the occupant's ribs.

[0005] An object of the present invention is to provide a side airbag device and a manufacturing method thereof that can improve the deployment behavior of the sub-chamber using a simple method to further enhance the safety of occupants.

[0006] A side airbag device according to one aspect of the present invention is an airbag that inflates and deploys to the side of an occupant seated in a vehicle seat, the airbag having a main chamber and a sub-chamber that inflates and deploys closer to the occupant than the main chamber, the main chamber and the sub-chamber communicating with each other via a communication hole, and an inflator that is provided in the main chamber and supplies gas for inflating and deploying the airbag, in a side airbag device that is such that, when the sub-chamber is deployed in a planar deployed state, its center in the vertical direction is located above the center of the communication hole, and the portion above the communication hole in the planar deployed state is folded back towards the occupant when in a stored state.

[0007] According to this aspect, when the sub-chamber is inflated and deployed by gas supplied from the inflator, the folded upper portion inflates and deploys by rising from the folded point. When the sub-chamber, which behaves like rising, acts on the occupant's arm, it lifts the occupant's arm from below. As a result, by simply folding the sub-chamber, the sub-chamber can move the occupant's arm away from the occupant's ribs, while the main chamber can restrain the occupant's entire body (for example, the area from the shoulders to the buttocks). This further improves the safety of the occupant when the airbag is inflated and deployed.

[0008] 1 is a side view showing an inflated and deployed state of a side airbag device according to an embodiment. FIG. 2 is a front view showing an inflated and deployed state of the side airbag device of FIG. 1. FIG. 3 is a side view showing the airbag of the side airbag device of FIG. 1 in a flat-laid state (flat deployed state) before folding the main chamber and the sub-chamber, and is a view illustrating the center of the sub-chamber in the up-down direction, etc. FIG. 4 is the same side view as FIG. 3, and is a view illustrating the configuration of the sub-chamber, etc. FIG. 5 is a side view showing the airbag of the side airbag device of FIG. 1 in a state after a portion of the sub-chamber has been folded. FIG. 6 is a front view showing the relationship between the side airbag device of FIG. 1 and the arm of an occupant, where (a) shows the stored state of the main chamber and the sub-chamber, and (b) shows the inflated and deployed state of the main chamber and the sub-chamber. FIG. 7 is a view showing the results of an inflation and deployment test of the side airbag device according to an embodiment over time. FIG. 8 is a view showing the results of an inflation and deployment test of a side airbag device according to a comparative example over time. FIG. 9 is a flowchart showing a manufacturing method of the side airbag device according to an embodiment.

[0009] A preferred embodiment of the present invention will be described with reference to the accompanying drawings. In this specification, up / down, left / right, and front / rear are defined as follows. When an occupant is seated in a seat in a normal posture, the direction the occupant faces is referred to as the forward direction, and the opposite direction is referred to as the rearward direction, and when indicating the coordinate axes, they are referred to as the front / rear direction or the vehicle's front / rear direction. Furthermore, when an occupant is seated in a seat in a normal posture, the right side of the occupant is referred to as the right direction, and the left side of the occupant is referred to as the leftward direction, and when indicating the coordinate axes, they are referred to as the left / right direction or the vehicle width direction. Similarly, when an occupant is seated in a normal posture, the direction of the occupant's head is referred to as the upward direction, and the direction of the occupant's waist is referred to as the downward direction, and when indicating the coordinate axes, they are referred to as the up / down direction.

[0010] In this document, "occupant" refers to a person with a physique equivalent to that of an average American male, conforming to the frontal crash test dummy (Hybrid III AM50 / frontal crash test dummy established by the NHTSA [National Highway Traffic Safety Administration] standard [49CFR Part 572 Subparts E and O]), with approximate dimensions of 175 cm in height, 88 cm in seated height, and 78 kg in weight.

[0011] As shown in Figures 1 and 2, a side airbag device 1 is provided on a seat 3 of a vehicle 2. The seat 3 is provided in a passenger compartment 4 of the vehicle 2. In this embodiment, the seat 3 is the left seat, but the side airbag device 1 can be attached to any seat. The seat 3 has a seat cushion 6, a seat back 7, and a headrest 8. The seat cushion 6 is provided on a floor 9 that forms the floor surface of the passenger compartment 4. The seat cushion 6 supports the buttocks of an occupant 100 from below. The seat back 7 extends upward from the rear of the seat cushion 6 and supports the back of the occupant 100 from behind. The headrest 8 is provided on the upper end of the seat back 7 and supports the head of the occupant 100 from behind.

[0012] 2, a door 11 of the vehicle 2 is provided on the left side of the seat 3, and a door trim 12 is provided on the interior side of the lower part of the door 11. The door trim 12 has an armrest 13 that protrudes inward in the vehicle width direction and extends forward and backward. A window opening 15 is provided at the top of the door 11, and a window glass 16 that can be raised and lowered is provided in the window opening 15.

[0013] Typically, a seating frame and a back frame (not shown) are provided inside the seat cushion 6 and the seat back 7, respectively, forming the framework of the seat 3. These frames are made of processed metal parts or hard resin and are connected to each other via a reclining mechanism. Pads are provided on and around the surfaces of these frames, and the surfaces of the pads are covered with a skin. The back frame has left and right side members that extend vertically and are spaced apart in the vehicle width direction, and the upper ends and lower ends of the left and right side members are connected to each other by an upper member and a lower member, respectively. Of the left and right side members, the side member on the outer side in the vehicle width direction has side wall portions extending in the front-to-rear direction and front and rear wall portions that extend short distances toward the vehicle interior from the front and rear ends of the side wall portions, and the side airbag device 1 is fixed to this side wall portion.

[0014] To explain one example, the side airbag device 1 is provided inside the seat back 7. At this time, the side airbag device 1 is stored in the space inside the pad that covers the periphery of the back frame of the seat back 7. The side airbag device 1 is then fixed to the surface of the side wall portion of the side member on the vehicle exterior side of the back frame that faces outward from the vehicle. There is a seam on the front side of the skin that covers the surface of the pad, and this seam ruptures when the side airbag device 1 is activated. This rupture causes the airbag 30 to inflate and deploy to the side of the occupant 100 (between the occupant 100 and the door 11).

[0015] The side airbag device 1 includes an airbag 30 that inflates and deploys to the side of an occupant 100 seated in a seat 3, and an inflator 33 that supplies inflation gas to the airbag 30. The airbag 30 has a main chamber 31 and a sub-chamber 32, and the sub-chamber 32 inflates and deploys closer to the occupant than the main chamber 31. The main chamber 31 and the sub-chamber 32 are in communication with each other via a communication hole 51. The inflator 33 is provided in the main chamber 31. Therefore, inflation gas from the inflator 33 is first supplied to the main chamber 31, and then instantly supplied from the main chamber 31 to the sub-chamber 32 via the communication hole 51.

[0016] The main chamber 31 inflates and deploys to a greater extent than the sub-chamber 32. The main chamber 31 and the sub-chamber 32 act differently on the occupant 100 when inflated and deployed. Specifically, the main chamber 31 primarily restrains the entire body of the occupant 100 when inflated and deployed, while the sub-chamber 32 primarily lifts the arms 110 (particularly the upper arms) of the occupant 100 when inflated and deployed. For example, the main chamber 31 inflates and deploys over a range that covers the shoulders to the buttocks of the occupant 100, while the sub-chamber 32 inflates and deploys over a range that first contacts the arms 110 of the occupant 100 and then contacts the torso of the occupant 110.

[0017] The main chamber 31 and the sub-chamber 32 are formed into a bag shape by joining (for example, sewing or gluing) one or more base fabrics made of, for example, nonwoven fabric at appropriate positions, or by weaving using OPW (One-Piece Woven). The main chamber 31 and the sub-chamber 32 are at least partially folded and stored inside the seat back 7. A case or a binding member such as tape that breaks upon predetermined inflation and deployment may be used to store the folded airbag 30.

[0018] The inflator 33 is electrically connected to an electronic control device (not shown) of the vehicle 2. The electronic control device supplies a predetermined current to the inflator 33 in the event of a side collision of the vehicle 2 (when it detects acceleration equal to or greater than a threshold value). The inflator 33 is activated when current is supplied from the electronic control device, and inflates and deploys the main chamber 31 and the sub-chamber 32. Various types of inflators can be used as the inflator 33, such as those filled with a gas generating agent, compressed gas, or both.

[0019] For example, the inflator 33 has a bottomed cylindrical body filled with a gas generating agent, an ignition device provided at the open end of the cylindrical body, and upper and lower stud bolts 33A, 33B provided on the outer periphery of the cylindrical body (see FIG. 3). Most of the inflator 33 is housed inside the main chamber 31, while the stud bolts 33A, 33B protrude outside the main chamber 31 and are fastened to the side wall of the side member with nuts. The inflator 33 is disposed to extend vertically parallel to the side member, and the lower end (ignition device) of the inflator 33 is connected to the electronic control device of the vehicle 2 by a wire harness. The ignition device ignites the gas generating agent inside the cylindrical body to generate gas, and the gas for inflation and deployment is supplied into the main chamber 31 from multiple nozzle holes on the circumferential surface of the cylindrical body.

[0020] Here, the main chamber 31 and the sub-chamber 32 can be roughly in a planar deployed state, a stored state, and an inflated and deployed state. Figures 3 and 3A show the planar deployed state of the main chamber 31 and the sub-chamber 32. The planar deployed state refers to a state in which the main chamber 31 and the sub-chamber 32 are laid flat before being folded and deployed in a plane. The planar deployed state is a state that the main chamber 31 and the sub-chamber 32 can be in before the side airbag device 1 is installed in the vehicle 2.

[0021] The stored state is the state after the side airbag device 1 is mounted on the vehicle 2 and before the main chamber 31 and the sub-chamber 32 are inflated and deployed. In the stored state, the sub-chamber 32 is folded. Also, in the stored state, the main chamber 31 may be folded. The folding method may be a roll shape, an accordion shape, or a combination of these. The folding method of the sub-chamber 32 is as described below. The inflated and deployed state is a state in which gas is supplied to the main chamber 31 and the sub-chamber 32, causing the main chamber 31 and the sub-chamber 32 to inflate and deploy.

[0022] Next, the main chamber 31 and the sub-chamber 32 in the flat deployed state will be described in detail using Figures 3 and 3A. The main chamber 31 and the sub-chamber 32 are flat, and most of the sub-chamber 32 is positioned so as to overlap the main chamber 31. Note that although the inflator 33 itself is not shown in Figures 3 and 3A, the positions of the upper and lower stud bolts 33A and 33B of the inflator 33 are shown on the main chamber 31. Below, we will first explain the center of each component in the vertical direction in the flat deployed state, and then explain the configuration and position of each part of each component.

[0023] 3 , the center 31O of the main chamber 31 in the up-down direction refers to the center that halves the vertical distance 31R between the top 31U and bottom 31L of the main chamber 31 in the planarly deployed state. Similarly, the center 32O of the sub-chamber 32 refers to the center that halves the vertical distance 32R between the top 32U and bottom 32L of the sub-chamber 32 in the planarly deployed state. The center 32O of the sub-chamber 32 is located above the center 31O of the main chamber 31 in the up-down direction.

[0024] The center 51A of the communication hole 51 is a position that halves the vertical distance between the top 51U and bottom 51L of the communication hole 51 in the up-down direction, and also halves the horizontal distance between the front 51F and rear 51R of the communication hole 51 in the front-to-rear direction. The center 51A of the communication hole 51 is preferably located at the same position as the center 31O of the main chamber 31 in the up-down direction, or lower than that.

[0025] The shape of the communication hole 51 is, for example, circular, and the center 51A is the center of the circle. In other embodiments, the shape of the communication hole 51 may be any shape, for example, rectangular or slit-shaped.

[0026] 3A , the center 32O of the sub-chamber 32 is located above the center 51A of the communicating hole 51 in the vertical direction. If the sub-chamber 32 is divided vertically using the position of the communicating hole 51 as the boundary, it can be said that the sub-chamber 32 has an upper portion 32A and a lower portion 32B. More specifically, the upper portion 32A corresponds to the portion located above an imaginary horizontal line 51B that passes through the upper end (uppermost portion 51U) of the communicating hole 51, and the lower portion 32B corresponds to the portion located below the horizontal line 51B. The upper portion 32A occupies a wider area of ​​the sub-chamber 32 than the lower portion 32B.

[0027] The lower portion 32B has a downwardly tapered shape. Here, the entire lower portion 32B is formed in a downwardly tapered shape. The lower end of the lower portion 32B has a downwardly curved portion 32C, a forward inclined portion 32D extending diagonally forward from the curved portion 32C, and a rearward inclined portion 32E extending diagonally rearward from the curved portion 32C. Here, the center 51A of the communication hole 51 is located in the center of the entire lower portion 32B in the front-to-rear direction. Specifically, the center 51A is located above the curved portion 32C. Furthermore, the position of the center 51A in the front-to-rear direction coincides or nearly coincides with the lowest end (lowermost portion 32L) of the curved portion 32C.

[0028] Comparing the subchamber 32 with the main chamber 31, the subchamber 32 is smaller than the main chamber 31 and overlaps the upper side of the main chamber 31. The subchamber 32 occupies a wide area forward of the center of the main chamber 31. Although the subchamber 32 does not extend beyond the upper, rear, and lower ends of the main chamber 31, a front end portion 32F of the subchamber 32 is located forward of the front end 31F of the main chamber 31. The front end portion 32F of the subchamber 32 that extends beyond the front end 31F of the main chamber 31 is mainly the front end portion of the upper portion 32A, but also includes an upper portion of the front end portion of the lower portion 32B.

[0029] Next, a state in which a portion of the sub-chamber 32 is folded will be described in detail with reference to Figure 4. This state may be the stowed state described above. When stowed in the seat back 7, the upper portion 32A is folded back from its flat, unfolded state toward the occupant 100 (the side opposite the main chamber 31) as shown in Figure 4. The folded portion, i.e., the fold 32I, is located on the imaginary horizontal line 51B used to explain the division between the upper portion 32A and the lower portion 32B.

[0030] In the stored state, the upper end 32G of the upper portion 32A of the sub-chamber 32 in its planar expanded state is located below the entire communicating hole 51, including the center 51A of the communicating hole 51. In addition, in the stored state, the upper end 32G is located below the lower end 32H of the lower portion 32B of the sub-chamber 32 in its planar expanded state. In the stored state, the upper end 32G extends obliquely downward and forward.

[0031] After first folding the upper portion 32A downward (toward the occupant) to store the sub-chamber 32, the sub-chamber 32 may be folded in any direction for storage. For example, the sub-chamber 32 can be stored in the seat back 7 by combining any folding methods, such as rolling it up from the bottom, folding it like an accordion, or folding it in half (or more) in the front-to-rear direction.

[0032] 5A and 5B are schematic diagrams showing the relationship between the side airbag device 1 and the arm 110 of the occupant 100 as viewed from the front side of the vehicle, in which FIG. 5A shows the main chamber 31 and the sub-chamber 32 in a stored state, and FIG. 5B shows the inflated and deployed state.

[0033] As shown in FIG. 5A, the side airbag device 1 is provided so that the folded portion 32I of the sub-chamber 32 and the communication hole 51 are positioned below the arm center 110A (elbow) of the occupant 100.

[0034] 5(b), when gas for inflation and deployment is supplied to the sub-chamber 32, the sub-chamber 32 unfolds the folded portion 32I, and the upper portion 32A of the sub-chamber 32 deploys by rising upward above the vehicle starting from the folded portion 32I. At this time, the upper portion 32A of the sub-chamber 32 comes into contact with the arm 110 of the occupant 100, particularly the upper arm portion of the arm 110, and lifts it up.

[0035] Next, the inflation and deployment test of the side airbag devices according to the embodiment and the comparative example will be described with reference to Figures 6 and 7. The comparative example differs from the embodiment in that the upper portion 32A of the sub-chamber 32 is not folded back toward the occupant 100 in the stored state.

[0036] As shown in Figure 6, in the side airbag device 1 according to this embodiment, when gas for inflation and deployment is supplied to the sub-chamber 32, the upper portion 32A of the sub-chamber 32 deploys so as to open upward from the folded portion 32I toward the top of the vehicle (see Figures 6(b) and 6(c)), and lifts the arm 110 of the occupant 100 (see Figures 6(d) and 6(e)).

[0037] In contrast, as shown in Figure 7, in the comparative example, when gas for inflation and deployment is supplied to the sub-chamber 32, the sub-chamber 32 is inflated and deployed toward the interior of the vehicle so that the entire sub-chamber 32 overlaps with the arm 110 of the occupant 100 (see Figures 7(b) and (c)), and presses the arm 110 toward the interior of the vehicle (see Figures 7(d) and (e)). The arm 110 of the occupant 100 is not lifted.

[0038] Next, a manufacturing method of the side airbag device 1 will be briefly described with reference to Figure 8. First, an airbag 30 having a main chamber 31 and a sub-chamber 32 is formed (S11). At this time, the sub-chamber 32 is formed so that, when the sub-chamber 32 is deployed in a plane, the center 32O of the sub-chamber 32 in the up-down direction is located above the center 51A of the communication hole 51 (see Figure 3A). Furthermore, when forming the sub-chamber 32, a downwardly tapered shape is formed in the lower portion 32B of the sub-chamber 32 when deployed in a plane.

[0039] Next, with the sub-chamber 32 and the main chamber 31 in their planar expanded states, the portion 32A of the sub-chamber 32 above the communication hole 51 in the planar expanded state is folded back toward the opposite side of the main chamber 31 (S12, see FIG. 4). The folded back location is the fold 32I described above. During this folding back, the upper end 32G of the upper portion 32A in the planar expanded state of the sub-chamber 32 is positioned below the center 51A of the communication hole 51, and further, is positioned below the lower end 32H of the lower portion 32B in the planar expanded state of the sub-chamber 32.

[0040] Next, the inflator 33 is provided in the main chamber 31 (S13). Note that this step (S12) may be performed before the step (S12) of folding back the upper portion 32A of the sub-chamber 32.

[0041] Thereafter, at least a portion of the sub-chamber 32 and / or the main chamber 31 is folded to store the airbag 30 (S14). Finally, the stud bolts 33A, 33B of the inflator 33 are fixed to the back frame of the seat back 7, thereby mounting the side airbag device 1 on the seat 3 (S15).

[0042] As described above, in the side airbag device 1 according to the embodiment, when deployed in a plane, the center 32O in the vertical direction of the sub-chamber 32 is located above the center 51A of the communication hole 51, and the portion 32A above the communication hole 51 in the deployed in a plane is folded back toward the occupant when in the stored state.

[0043] According to this aspect, when the sub-chamber 32 is inflated and deployed by gas supplied from the inflator 33, the folded upper portion 32A inflates and deploys by rising from the folded portion (folded portion 32I). When the sub-chamber 32, which behaves like rising, acts on the arm 110 of the occupant 100, it lifts the arm 110 of the occupant 100 from below. As a result, by simply folding the sub-chamber 32, the sub-chamber 32 can move the arm 110 of the occupant 100 in a direction away from the ribs of the occupant 100, while the main chamber 31 can restrain the entire body of the occupant 100 (for example, the area from the shoulders to the buttocks). This further improves the safety of the occupant 100 when the airbag 30 is inflated and deployed.

[0044] Furthermore, the lower portion 32B of the sub-chamber 32 in its flat deployed state has a shape that tapers downward, which makes it easier for gas supplied from the inflator 33 to flow from the bottom to the top of the sub-chamber 32 when the airbag 30 is inflated and deployed. This can encourage deployment of the upper portion 32A, which opens upward starting from the folded portion 32I.

[0045] Furthermore, in the stored state, the upper end 32G of the upper portion 32A of the sub-chamber 32 in its deployed state is located below the center 51A of the communication hole 51 or the entire communication hole 51. This allows the upper portion 32A of the sub-chamber 32 to be located as low as possible (ensuring its length) in the stored state, making it easier for the occupant 100 to lift their arm 110 even if they are shifted away from the sub-chamber 32.

[0046] Furthermore, in the sub-chamber 32, the upper portion 32A occupies a wider area than the lower portion 32B. This allows the upper portion 32A to be made larger within the limited area of ​​the sub-chamber 32, so that the upper portion 32A can press against and lift the arm 110 of the occupant 100 over a wider surface. Furthermore, by making the lower portion 32B smaller, when the sub-chamber 32 inflates and deploys, the inflation gas from the inflator 33 can reach the upper portion more quickly from the lower portion. This allows the upper portion 32A to rise up more quickly.

[0047] Furthermore, the front end portion 32F of the sub-chamber 32 in its flat deployed state is located further forward than the front end 31F of the main chamber 31 in its flat deployed state. As a result, the upper portion 32A of the sub-chamber 32 is longer toward the front of the vehicle, making it easier to push and lift the arms 110 of the occupant 100 further forward. Also, occupants of different builds can easily lift their arms with the same layout.

[0048] The above-described embodiments are intended to facilitate understanding of the present invention and are not intended to limit the present invention. The elements of the embodiments, as well as their arrangement, materials, conditions, shapes, sizes, etc., are not limited to those exemplified and can be modified as appropriate.

[0049] Additional Considerations Regarding Various Embodiments

[0050] [Embodiment 1] A side airbag device comprising: an airbag that inflates and deploys to the side of an occupant seated in a vehicle seat, the airbag having a main chamber and a sub-chamber that inflates and deploys closer to the occupant than the main chamber, the main chamber and the sub-chamber communicating with each other via a communication hole; and an inflator that is provided within the main chamber and supplies gas for inflating and deploying the airbag, wherein the center of the sub-chamber in the vertical direction when deployed in a plane is located above the center of the communication hole, and the portion above the communication hole when deployed in a plane is folded back towards the occupant when stored.

[0051] [Embodiment 2] The side airbag device according to embodiment 1, wherein a lower portion of the sub-chamber in a flat deployed state has a downwardly tapered shape.

[0052] [Embodiment 3] The side airbag device of embodiment 2, wherein the lower portion is located below an imaginary horizontal line passing through an upper end of the communication hole, and the entire lower portion is formed in the tapered shape.

[0053] [Embodiment 4] The side airbag device according to embodiment 2 or 3, wherein the center of the communication hole is located at the center of the entire lower portion in the front-rear direction.

[0054] [Embodiment 5] A side airbag device according to any one of embodiments 2 to 4, wherein the lower end of the lower portion has a downward curved portion, a forward inclined portion extending diagonally forward from the curved portion, and a rearward inclined portion extending diagonally rearward from the curved portion, and the center of the communication hole is located above the curved portion.

[0055] [Embodiment 6] A side airbag device according to any one of embodiments 1 to 5, wherein the upper end of the upper portion of the sub-chamber in the flat deployed state is located below the center of the communication hole in the stored state.

[0056] [Embodiment 7] A side airbag device according to any one of embodiments 1 to 5, wherein an upper end of the upper portion of the sub-chamber in the flat deployed state is located lower than the entire communicating hole in the stored state.

[0057] [Embodiment 8] The side airbag device according to embodiment 6 or 7, wherein the upper end extends obliquely downward toward the front in the stored state.

[0058] [Embodiment 9] A side airbag device according to any one of embodiments 1 to 8, wherein an upper end of the upper portion of the sub-chamber in the flat deployed state is located lower than a lower end of the sub-chamber in the flat deployed state in the stored state.

[0059] [Embodiment 10] A side airbag device according to any one of embodiments 1 to 9, wherein the upper portion is a portion located above an imaginary horizontal line passing through the upper end of the communication hole, and the upper portion occupies a wider area in the sub-chamber than the portion located below the horizontal line.

[0060] [Embodiment 11] A side airbag device according to any one of embodiments 1 to 10, wherein a front end portion of the sub-chamber in a flat deployed state is located forward of a front end of the main chamber in a flat deployed state.

[0061] [Embodiment 12] The side airbag device according to any one of embodiments 1 to 11, wherein, in a flat deployed state, the sub-chamber occupies a wide area forward of the center of the main chamber.

[0062] [Embodiment 13] A method for manufacturing a side airbag device comprising: an airbag that inflates and deploys to the side of an occupant seated in a vehicle seat, the airbag having a main chamber and a sub-chamber that inflates and deploys closer to the occupant than the main chamber, the main chamber and the sub-chamber communicating with each other via a communication hole; and an inflator provided in the main chamber and supplying gas for inflating and deploying to the airbag, the method comprising: forming the sub-chamber so that, when the sub-chamber is in a planar deployed state, the center of the sub-chamber in the vertical direction is located above the center of the communication hole; folding back, when the sub-chamber and the main chamber are in a planar deployed state, the portion of the sub-chamber that is above the communication hole in the planar deployed state, to the opposite side from the main chamber; and folding down at least a portion of the sub-chamber and / or the main chamber to store the airbag.

[0063] [Embodiment 14] The side airbag device according to claim 13, wherein the step of forming the sub-chamber includes forming a downwardly tapered shape in a lower portion of the sub-chamber in a flat deployed state.

[0064] [Embodiment 15] The method for manufacturing a side airbag device according to claim 14, wherein the folding back step includes positioning an upper end of the upper portion of the sub-chamber in a planar deployed state below a center of the communication hole.

[0065] 1...side airbag device, 2...vehicle, 3...seat, 4...vehicle compartment, 6...seat cushion, 7...seat back, 8...headrest, 9...floor, 11...door, 12...door trim, 13...armrest, 15...window opening, 16...window glass, 30...airbag, 31...main chamber, 31F...front end, 31U...top, 31L...bottom, 31O...center, 31R...distance, 32...sub-chamber, 32A...upper portion, 32B...lower portion, 32C...curved portion, 32D... Forward inclined portion, 32E...rear inclined portion, 32F...front end portion, 32G...upper end, 32H...lower end, 32I...folded portion, 32U...top portion, 32L...bottom portion, 32O...center, 32R...distance, 33...inflator, 33A...upper stud bolt, 33B...lower stud bolt, 51...communication hole, 51A...center of communication hole, 51B...imaginary horizontal line, 51U...top portion, 51L...bottom portion, 51F...foremost portion, 51R...rearmost portion, 100...occupant, 110...occupant's arm, 110A...arm center

Claims

1. A side airbag device comprising: an airbag that inflates and deploys to the side of an occupant seated in a vehicle seat, the airbag having a main chamber and a sub-chamber that inflates and deploys closer to the occupant than the main chamber, the main chamber and the sub-chamber communicating with each other via a communication hole; and an inflator that is provided within the main chamber and supplies gas for inflating and deploying the airbag, wherein the center of the sub-chamber in the vertical direction when deployed in a plane is located above the center of the communication hole, and the portion above the communication hole when deployed in a plane is folded back towards the occupant when stored.

2. The side airbag device according to claim 1, wherein a lower portion of the sub-chamber in a flat deployed state has a downwardly tapered shape.

3. A side airbag device as set forth in claim 2, wherein the lower portion is located below an imaginary horizontal line passing through the upper end of the communication hole, and the entire lower portion is formed in the tapered shape.

4. The side airbag device according to claim 3, wherein the center of the communication hole is located at the center of the entire lower portion in the front-rear direction.

5. A side airbag device as described in claim 2, wherein the lower end of the lower section has a downwardly curved portion, a forward inclined portion extending diagonally forward from the curved portion, and a rearward inclined portion extending diagonally rearward from the curved portion, and the center of the communication hole is located above the curved portion.

6. The side airbag device according to claim 1, wherein the upper end of the upper portion of the sub-chamber in the deployed state is located below the center of the communication hole in the stored state.

7. The side airbag device according to claim 1, wherein the upper end of the upper portion of the sub-chamber in the deployed state is located lower than the entire communicating hole in the stored state.

8. A side airbag device according to claim 6 or 7, wherein the upper end extends obliquely downward toward the front in the stored state.

9. A side airbag device according to any one of claims 1 to 5, wherein the upper end of the upper portion of the sub-chamber in its flat deployed state is located lower than the lower end of the sub-chamber in its flat deployed state in its stored state.

10. A side airbag device as claimed in any one of claims 1 to 7, wherein the upper portion is a portion located above an imaginary horizontal line passing through the upper end of the communication hole, and the upper portion occupies a wider area of ​​the sub-chamber than the portion located below the horizontal line.

11. A side airbag device according to any one of claims 1 to 7, wherein the front end portion of the sub-chamber in its flat deployed state is located forward of the front end of the main chamber in its flat deployed state.

12. A side airbag device according to any one of claims 1 to 7, wherein, in a flat deployed state, the sub-chamber occupies a wide area forward of the center of the main chamber.

13. A method for manufacturing a side airbag device comprising: an airbag that inflates and deploys to the side of an occupant seated in a vehicle seat, the airbag having a main chamber and a sub-chamber that inflates and deploys closer to the occupant than the main chamber, the main chamber and the sub-chamber communicating with each other via a communication hole; and an inflator provided in the main chamber and supplying gas for inflating and deploying to the airbag, the method comprising the steps of: forming the sub-chamber so that, when the sub-chamber is in a planar deployed state, the center of the sub-chamber in the vertical direction is located above the center of the communication hole; folding back, when the sub-chamber and the main chamber are in a planar deployed state, the portion of the sub-chamber that is above the communication hole in the planar deployed state, to the opposite side from the main chamber; and folding down at least a portion of the sub-chamber and / or the main chamber to store the airbag.

14. A method for manufacturing a side airbag device according to claim 13, wherein the step of forming the sub-chamber includes forming a downwardly tapered shape in a lower portion of the sub-chamber in a flat deployed state.

15. The method for manufacturing a side airbag device according to claim 14, wherein the folding back step includes positioning the upper end of the upper portion of the sub-chamber in its flat deployed state below the center of the communication hole.

Images