Occupant protection devices

Abstract

To provide an occupant protection device which can quickly protect the upper body of an occupant with an air bag that has been inflated.SOLUTION: There is provided an occupant protection device which is configured to protect an occupant seated on a seat. An air bag 25 is held by a holding body which is arranged in the periphery of the lumbar part of the occupant. The air bag includes: a bag body 26; and a conduit pipe part 50 which makes inflation gas discharged from an inflator into the bag body. The bag body is held by the holding body in a state of the folding completion body in which the bag body is folded by front-rear shrinkage folding such that the width dimension on the front-rear direction side shrinks from a state of a preliminary folded bag 70. The folding completion body is formed by overlapping a lower side roll folding portion 77 that is formed such that a lower side portion 74 that becomes the lower side with respect to the conduit pipe part in the preliminary folded bag is rolled from the lower edge side on an upper side roll folding portion 76 that is formed such that an upper side portion 73 that becomes the upper side with respect to the conduit pipe part in the preliminary folded bag is rolled from the upper edge side.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to an occupant protection device for protecting an occupant seated in a seat. [Background technology]

[0002] Conventionally, there has been an occupant protection device configured to house a folded airbag in a portion of a seatbelt that is wound around the waist, and to protect an occupant seated in a seat with the inflated airbag (see, for example, Patent Document 1). Specifically, in the conventional occupant protection device, the airbag is configured to include a bag body that is positioned to cover the front of the occupant when fully inflated, and a conduit portion that allows inflation gas discharged from an inflator to flow into the bag body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2020-66425 Summary of the Invention [Problem to be solved by the invention]

[0004] In this conventional passenger protection device, the bag body has an outer shape of a generally triangular prism with its axial direction generally aligned with the left-right direction when fully inflated, and the bag body, which is folded and stored in the area of ​​the lap belt, is inflated by flowing inflation gas into the bag body so that it protrudes forward and upward. In this conventional passenger protection device, the bag body is configured to protect the upper body of the passenger when fully inflated, and it is desirable for it to inflate quickly to cover the front of the upper body.

[0005] SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has an object to provide an occupant protection device that can quickly protect the upper body of an occupant with an airbag that has completed inflation. [Means for solving the problem]

[0006] The occupant protection device according to the present invention is configured to protect an occupant seated in a seat, The airbag is configured to include an airbag, a holder that is disposed around the waist of an occupant and that stores and holds the folded airbag, and an inflator that supplies inflation gas to the airbag, The airbag, a bag body that is disposed so as to cover the front of the occupant when inflation is complete; a conduit portion connected to the inflator for allowing inflation gas discharged from the inflator to flow into the bag body through the communication hole; With An occupant protection device in which a bag body inflates while protruding forward and upward from a holder, and the bag body has an outer shape at the time of complete inflation that is a substantially triangular prism shape with an axial direction substantially aligned with the left-right direction, and the bag body is configured to include a front wall portion that is located on the front side away from an occupant at the time of complete inflation, and a rear wall portion and a lower wall portion that are located on the occupant side at the time of complete inflation, The bag body is held by the holder in a fully folded state in which the bag body is folded by front-to-back contraction folding so as to reduce the width dimension in the front-to-back direction from a pre-folded bag state in which the bag body is laid out flat over substantially the entire area of ​​the front wall portion and overlapped on the rear wall portion and the lower wall portion, The folded body is characterized in that a lower roll-folded portion formed by winding a lower portion of the pre-folded bag below the conduit section from the lower edge side toward the front wall side is superimposed on an upper roll-folded portion formed by winding an upper portion of the pre-folded bag above the conduit section from the upper edge side toward the front wall side.

[0007] In the occupant protection device of the present invention, the bag body of the airbag is held by the holder in a folded state such that a lower rolled-up portion formed by folding a lower portion of the pre-folded bag that is below (forward of) the conduit portion (i.e., the region of the bag body toward the lower wall portion at the time of full inflation) is overlapped over an upper rolled-up portion formed by folding an upper portion of the pre-folded bag that is above (rearward of) the conduit portion (i.e., the region of the bag body toward the rear wall portion at the time of full inflation). Therefore, when inflation gas discharged from the inflator flows into the bag body through the conduit portion and the communication hole and the bag body inflates, the inflation gas flowing into the bag body from the communication hole pushes up the lower rolled-up portion and the upper rolled-up portion, but the overlapping lower rolled-up portion first unfolds and inflates while protruding forward and upward from the holder, and then the upper rolled-up portion unfolds and inflates. In other words, in the occupant protection device of the present invention, the front lower region of the bag body inflates first while unfolding, and the rear upper region, which is located in front of the occupant's upper body when inflation is complete, is prevented from protruding forward away from the occupant by the front lower region, which inflates first, so that the rear upper region protrudes upward and can inflate at a position close to and in front of the occupant's upper body. Therefore, the inflated bag body can quickly cover the front of the occupant's upper body and quickly restrain the occupant's shoulders, head, etc.

[0008] Therefore, in the passenger protection device of the present invention, the upper body of the passenger can be quickly protected by the airbag that has completed inflation.

[0009] In the passenger protection device of the present invention, the bag body is folded by first being folded in a left-right contraction manner so as to reduce the width dimension of the pre-folded bag in the left-right direction, and then being folded by being folded in a front-rear contraction manner, It is preferable that the left and right shrink-folded bag is formed by overlapping the left and right edges of the pre-folded bag with each other.

[0010] By configuring the occupant protection device in this manner, the folded body can be formed compactly on the left and right. Therefore, even if, for example, the folded body is positioned slightly off to the left or right relative to the seat due to differences in the physiques of the occupants sitting in the seat, the influence of such positional deviation can be suppressed, and the bag body can be inflated quickly without being affected by the seat or the like. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a perspective view of a seat equipped with an occupant protection device according to an embodiment of the present invention; [Figure 2] FIG. 2 is a side view of the seat of FIG. 1. [Figure 3] FIG. 2 is a front view of the seat of FIG. 1, showing the state in which the seat belt is fastened. [Figure 4] 1 is a schematic perspective view showing an airbag used in an occupant protection device according to an embodiment in a state where the airbag is inflated by itself; [Figure 5] FIG. 5 is a schematic vertical cross-sectional view of the airbag of FIG. 4. [Figure 6] FIG. 5 is a plan view showing the arrangement of base materials that constitute the airbag of FIG. 4. [Figure 7] 5 is a schematic view illustrating a process of forming a tuck portion in the airbag of FIG. 4. FIG. [Figure 8] 5 is a schematic diagram illustrating a folding process of the airbag of FIG. 4. FIG. [Figure 9] 3A to 3C are schematic diagrams illustrating an inflation process of an airbag in the occupant protection device according to the embodiment. [Figure 10] 10 is a schematic diagram illustrating the inflation process of the airbag, illustrating the process subsequent to that of FIG. 9. FIG. [Figure 11] 1 is a front view of a seat in a state where an airbag has completed inflation in an occupant protection device according to an embodiment; [Figure 12] 1 is a side view of a seat in a state where an airbag has completed inflation in an occupant protection device according to an embodiment; DETAILED DESCRIPTION OF THE INVENTION

[0012] An embodiment of the present invention will be described below with reference to the drawings. As shown in Figures 1 to 3, an occupant protection device S of the embodiment is mounted on a vehicle seat 1 and includes a seat belt 7 constituting a holder for holding an airbag 25, the airbag 25, and an inflator 17 for supplying inflation gas to the airbag 25. The seat 1 includes a backrest 2 and a seat portion 3. In the embodiment, the front-rear, up-down, left-right directions correspond to the front-rear, up-down, left-right directions of the seat 1 unless otherwise specified.

[0013] In this embodiment, the seat belt 7 is mounted on the seat 1 and includes a belt body 8 for restraining an occupant MP seated in the seat 1, a tongue plate 12 attached to the belt body 8, and a buckle 13 for connecting the tongue plate 12. One end of the belt body 8 is fastened to a winding shaft of a retractor (not shown) disposed in the backrest 2, and the other end is fastened to an anchor member 14 (see FIGS. 1 and 2) disposed to the left of the rear end 3b of the seat portion 3 of the seat 1. More specifically, the belt body 8 is disposed so as to be exposed to the outside from the upper left edge side of the backrest 2. In this embodiment, when the occupant MP is not seated, the lap belt 10, which serves as a retainer for retaining the airbag 25, is exposed to the front surface of the backrest 2 as shown in FIGS. 1 and 2. 1, when the occupant MP is not seated, the lap belt 10 is exposed at the front of the backrest 2 on the left edge 2a side of the backrest 2 so as to extend substantially along the vertical direction. The belt main body 8 has the lap belt 10 and a shoulder belt 9 stored in the backrest 2, and when the occupant MP is seated, with the tongue plate 12 connected to the buckle 13, the lap belt 10, which is disposed substantially along the horizontal direction between the anchor member 14 and the buckle 13, restrains the lower body MD (lumbar region MW) of the occupant MP, and the shoulder belt 9, which extends from the upper left edge of the backrest 2 and is disposed diagonally to the buckle 13, restrains the upper body MU (from the shoulders MS to the chest MB) of the occupant MP (see FIG. 3). In this embodiment, when an occupant MP is seated, the lap belt 10, which is placed in front of the waist MW of the occupant MP seated in the seat 1, and a cover 22, which will be described later, form a holder that stores and holds the folded airbag 25. In the seat belt 7, a retractor (not shown) that is placed in the backrest 2 has a pretensioner mechanism.

[0014] The inflator 17 is mounted on the seat 1, and more specifically, in this embodiment, is disposed at a position below the seat surface 3a of the seat 1. In this embodiment, as shown in FIG. 2, the inflator 17 includes an inflator body 18 (detailed illustration omitted) having a generally cylindrical outer shape, and a pipe portion 19 extending from the inflator body 18 to supply inflation gas to the airbag 25. The pipe portion 19 extends from the inflator body 18 and is disposed so that its tip is positioned near the boundary between the seat portion 3 and the backrest 2 on the left side of the seat 1, and this tip is configured to be connected to a conduit portion 50 of the airbag 25 (described later) using a clamp 20 (see FIG. 12). In this embodiment, the inflator 17 (inflator body 18) is configured to start operating later than the pretensioner mechanism of the seatbelt 7 in order to restrict the belt body 8 of the seatbelt 7 from being pulled out due to the inflation of the airbag 25. Specifically, the inflator 17 is set to operate 5 ms after the pretensioner mechanism of the seat belt 7 is activated.

[0015] The airbag 25 is held by the lap belt 10 of the seat belt 7 as a holder, folded into a long shape, and covered by the cover 22. Specifically, when the bag body 26 described below is folded into a fully folded state 80, the airbag 25 is placed in the area of ​​the lap belt 10, overlapping the upper surface of the lap belt 10 when the seat belt 7 is worn, and is covered by the cover 22 (see FIG. 3). In other words, the airbag 25 (bag body 26) is configured to be stored in the gap between the lap belt 10 and the cover 22 when in the fully folded state 80. In addition, in the unworn state as shown in FIG. 1, the airbag 25 is located on the back side (backrest 2 side) of the lap belt 10 exposed at the front of the backrest 2. The cover 22 is made of a flexible sheet and is configured to be torn at a predetermined location when the airbag 25 is deployed and inflated, allowing the bag body 26 of the airbag 25 to protrude.

[0016] The airbag 25 is a bag-shaped body formed from a flexible sheet, and as shown in Figures 4 and 5, it includes a bag body 26 and a conduit portion 50 that is connected to the inflator 17 and allows inflation gas to flow into the bag body 26.

[0017] In this embodiment, the bag body 26 has an outer shape at full inflation that is generally triangular prism-shaped, with its axial direction generally aligned with the left-right direction and its width increasing from front to back toward its lower end, as shown in FIGS. 5 and 12. In this embodiment, the bag body 26 is bent at its upper and lower intermediate portions so that its upper end 26a at full inflation faces rearward toward the occupant MP. Furthermore, in this embodiment, the bag body 26 is configured such that, as shown in FIG. 11, its fully inflated shape is widest below the center in the vertical direction, and the upper region of this wide portion 27 (slightly below the center in the vertical direction) is narrowed by being significantly constricted. This narrow-width portion 28 is positioned corresponding to the chest MB of the occupant MP (see FIG. 11). When viewed from the front-rear direction, the inflated bag body 26 has a width that gradually decreases in the left-right direction from the wide portion 27 toward the lower end (front lower end 26b) and gradually increases in the left-right direction from the narrow portion 28 toward the upper end 26a (see FIG. 11 ). The bag body 26 includes a rear wall portion 37 and a lower wall portion 33 that are positioned toward the occupant MP when fully inflated, a front wall portion 32 that is positioned forward and away from the occupant MP when fully inflated, and a left wall portion 34 and a right wall portion 35 that are positioned opposite each other in the left-right direction when fully inflated. A bent portion 38 is positioned in the vertical middle of the rear wall portion 37, so that the upper end 26a when fully inflated protrudes toward the occupant MP (rearward) (see FIGS. 5 and 12 ). As shown in FIG. 11 , the bent portion 38 is formed in the region of the narrow portion 28 of the bag body 26. Vent holes 40 that can exhaust excess inflation gas that has flowed inside are formed in the left wall portion 34 and the right wall portion 35. More specifically, the vent holes 40 are formed below the center of the left wall portion 34 and the right wall portion 35 in the vertical direction, on the leading edge side.

[0018] In the bag body 26 of this embodiment, the lower surface 33a of the lower wall portion 33 forms a supported surface 43 that abuts against and is supported by the thighs MT of the occupant MP when the bag body 26 receives the upper body MU of the occupant MP upon full inflation (see FIG. 12). The bag body 26 is configured to communicate with the conduit 50 via the communication hole 41 at a portion on the rear lower end 26c side (a portion on the rear end side of the lower wall portion 33) upon full inflation, and the supported surface 43 is configured from an area of ​​the lower wall portion 33 that is forward of the conduit 50 (base-side portion 51). The lower wall portion 33 (supported surface 43) is positioned with a downward tilt toward the front when the bag body 26 is fully inflated and before receiving the occupant (see FIG. 12). In this embodiment, the communication holes 41 that connect the conduit portion 50 and the bag body 26 are circular openings, and two of them are provided side by side on the left and right sides (see FIGS. 4 and 6).

[0019] Furthermore, the rear wall 37 of the bag main body 26 of the embodiment constitutes an upper body restraint surface 44 that can restrain the upper body MU of the occupant MP when inflation is complete (see FIG. 12). The upper body restraint surface 44 includes a lower restraint surface 44b that can restrain the area from the abdomen MA to the thorax MB of the occupant MP, and an upper restraint surface 44a that can restrain the head MH or shoulders MS (head MH in this embodiment) of the occupant MP. Furthermore, in the bag main body 26 of the embodiment, a bent portion 38 is disposed at the boundary between the upper restraint surface 44a (upper portion 37a) and the lower restraint surface 44b (lower portion 37b) of the rear wall 37. This bent portion 38 positions the upper restraint surface 44a (upper portion 37a) so that it protrudes toward the occupant MP (rearward) relative to the lower restraint surface 44b (lower portion 37b) when inflation of the bag main body 26 is complete (see FIGS. 5 and 12). In this embodiment, the bent portion 38 is composed of tuck portions 39 formed by pinching and joining the rear wall portion 37 at positions spaced apart from each other in the vertical direction.

[0020] Specifically, the tuck portion 39 is formed in a substantially oval tuck formation portion 61d (see FIG. 6) that is generally aligned along the left-right direction when an upper portion 61 of an occupant-side panel 60 (described later) that constitutes the rear wall 37 is laid out flat, and is formed by partially pinching and folding the upper portion 61 in half, and then sewing (joining) the tuck formation portion 61d to join the upper portion 61 (rear wall 37) together, as shown in FIG. 7. In this embodiment, the tuck portion 39 is formed so as to protrude forward of the rear wall 37 (inside the bag main body 26) (see FIG. 5), and is positioned in the region of the narrow width portion 28 of the bag main body 26 when inflation is complete, in front of the chest MB of the occupant MP (see FIGS. 11 and 12). In addition, in this embodiment, the width dimension W1 of the left-right side of the tuck portion 39 (tuck formation portion 61d) is set to approximately half the width dimension W2 of the left-right side of the narrow width portion 28 when the rear wall portion 37 (upper portion 61 of the occupant side panel 60) is laid out flat (see Figure 6).

[0021] In the bag body 26 of this embodiment, in a longitudinal cross section generally along the front-rear direction when the bag body 26 is inflated by itself, the intersecting angle α between the tangents of the upper restraining surface 44a (upper portion 37a of the rear wall portion 37) and the lower restraining surface 44b (lower portion 37b of the rear wall portion 37) is set to about 130° (see FIG. 5). Also, the intersecting angle β between the tangents of the lower wall portion 33 (supported surface 43) and the lower portion 36b (lower restraining surface 44b) when the bag body 26 is inflated by itself is set to about 130° (see FIG. 5). In this embodiment, the bag body 26 has a width dimension in the front-to-rear direction at its lower end when fully inflated such that the front end of the lower wall 33 (the front lower end 26b of the bag body 26) is positioned slightly behind the knees MK of the occupant MP, and a width dimension in the up-down direction at its rear end when fully inflated such that the upper end 26a (the upper end of the rear wall 37) is positioned in front of the head MH of the occupant MP (see FIG. 12). The bag body 26 also has a width dimension in the left-to-right direction at its fully inflated state that is smaller than the backrest 2 of the seat 1, and a wide region that is approximately the same width as the upper body MU of the occupant MP so as to stably protect the upper body MU of the occupant MP (see FIG. 11).

[0022] The conduit 50 extends leftward from the bag body 26, has a generally cylindrical shape with an open tip, and is configured to connect to the pipe 19 of the inflator 17. The conduit 50 is disposed generally along the left-right direction so as to generally follow the lap belt 10 when the airbag 25 is fully inflated. A base portion 51 disposed on the underside of the bag body 26 is wider than a tip portion 52 disposed on the left side of the bag body 26 and connected to the inflator 17. The conduit 50 communicates with the bag body 26 at the base portion 51 through a communication hole 41. In this embodiment, the conduit 50 and the bag body 26 are connected by sewing the periphery of the communication hole 41. The airbag 25 of this embodiment is attached to the lap belt 10 by sewing the base portion 51 of the conduit 50 directly to the lap belt 10 (see FIG. 5). Conduit 50 has upper wall 54 and lower wall 55 arranged opposite each other in the vertical direction, and specifically, the base side region of lower wall 55 (the region constituting base side region 51) is sewn to lap belt 10 with a sewing thread. In this embodiment, stitching region 57 that sews lap belt 10 and conduit 50 together is formed in the shape of a double line that is substantially along the length of lap belt 10 (see the two-dot chain line in FIGS. 4 and 7).

[0023] 6, the airbag 25 of this embodiment is constructed by joining the peripheral edges of a base fabric of a predetermined shape, and in this embodiment, as shown in Fig. 6, is composed of an occupant-side panel 60 and a front-side panel 65 that constitute the bag body 26, and two conduit panels 67, 68 that constitute the conduit 50. The occupant-side panel 60, the front-side panel 65, and the conduit panels 67, 68 are each formed from flexible woven fabric made of polyester yarn, polyamide yarn, or the like.

[0024] The occupant-side panel 60 is disposed on the occupant MP side when inflation is complete, and mainly constitutes the region from the rear wall portion 37 to the lower wall portion 33. Specifically, the occupant-side panel 60 includes an upper portion 61 that mainly constitutes the rear wall portion 37, and a lower portion 62 that mainly constitutes the lower wall portion 33, and has an outer shape such that the upper portion 61 and the lower portion 62 are connected at a portion that constitutes the rear lower end 26c of the bag main body 26. The upper portion 61 constitutes the rear wall portion 37 and rear regions of the left wall portion 34 and right wall portion 35. The lower portion 62 constitutes the lower wall portion 33 and lower regions of the left wall portion 34 and right wall portion 35. The front panel 65 mainly constitutes the front wall 32 of the bag body 26 when fully inflated (specifically, the front regions of the front wall 32, left wall 34, and right wall 35), and is configured so that its outer shape when flattened out substantially matches that of the lower region 62 and upper region 61 when the occupant-side panel 60 is opened to separate the remaining connected edges (upper edge 61c, front edge 62c) of the lower left edge 61a and rear left edge 62a, and the lower right edge 61b and rear right edge 62b, which are located on the left and right of the connecting portion 60a connecting the upper region 61 and the lower region 62 of the occupant-side panel 60. The front panel 65 and the occupant-side panel 60 are each symmetrical. The bag body 26 of the embodiment is made bag-shaped by joining the outer peripheral edge 65a of the front panel 65 to the upper edge 61c and front edge 62c of the occupant side panel 60 in a state in which the lower left edge 61a and rear left edge 62a, and the lower right edge 61b and rear right edge 62b are joined together as described above.

[0025] The two conduit section panels 67, 68 have the same outer shape and constitute the upper wall section 54 and the lower wall section 55 of the conduit section 50, respectively.

[0026] Next, the folding of the airbag 25 of this embodiment will be described. The airbag 25 is held by the lap belt 10 in a fully folded state 80 formed by folding a pre-folded bag 70, which is formed by folding the bag body 26 so that it unfolds flat, through left-right contraction folding to reduce the width dimension in the left-right direction and front-rear contraction folding to reduce the width dimension in the front-rear direction. The pre-folded bag 70 is formed by unfolding the front panel 65 (front wall portion 32) flat over substantially the entire area and overlapping it on the occupant-side panel 60 (rear wall portion 37, lower wall portion 33). In detail, the pre-folded bag 70 is formed by folding the upper portion 61 of the occupant-side panel 60 across the entire left-right area with a crease substantially along the left-right direction, so that the front panel 65 is unfolded flat over the entire area (see A in FIG. 8). Thereafter, left and right edges 70a and 70b of the preparatory-folded bag 70 are folded back toward the front panel 65 (the side away from the occupant) to form a left and right shrink-folded bag 72. In this left and right shrink-folded bag 72, the left and right edges 70a and 70b of the preparatory-folded bag 70 are overlapped with each other. In detail, as shown in FIG. 8B , the preparatory-folded bag 70 is folded near the edge of the communication hole 41 to form a crease that is approximately along the front-rear direction, with the left and right edges 70a and 70b overlapping in the wide portion. Thereafter, the left and right shrink-folded bag 72 is folded by front-rear shrinking folds that reduce the width dimension in the front-rear direction. 8B and 8C, in left-right shrink-folded bag 72, upper region 73, which is above (rear of) conduit 50 (base region 51), is rolled from upper edge 73a toward front panel 65 (front wall 32) to form upper rolled fold region 76, and upper rolled fold region 76 is placed on base region 51 of conduit 50. Similarly, lower region 74, which is below (front of) conduit 50, is rolled from lower edge 74a toward front panel 65 (front wall 32) to form lower rolled fold region 77, which is placed on top of upper rolled fold region 76, thereby folding bag body 26.The completely folded body 80 formed by folding the bag main body 26 in this manner is placed on top of the base portion 51 of the conduit 50, and a breakable anti-fold tape (reference number omitted) is wound around the base portion 51 and the base portion 51 at predetermined locations to maintain the folded state, as shown in Fig. 8C. The base portion 51 of the conduit 50 is sewn to the lap belt 10, and the completely folded body 80 is held by the lap belt 10, and is covered by the cover 22 together with the lap belt 10, and is positioned in the area of ​​the lap belt 10.

[0027] In the embodiment of the occupant protection device S, when the inflator 17 is activated while the occupant MP is seated in the seat 1 mounted in the vehicle and wearing the seat belt 7, the inflation gas discharged from the inflator 17 flows into the bag body 26 through the conduit portion 50, causing the bag body 26 to break the cover 22 and protrude forward and upward from the lap belt 10, completing inflation as shown by the two-dot chain line in Figure 3 and Figures 11 and 12.

[0028] In the occupant protection device S of the embodiment, the bag body 26 of the airbag 25 is held in a folded state by the lap belt 10 as a holder, with the lower rolled fold portion 77 formed by folding the lower portion 74 below the conduit portion 50 of the pre-folded bag 70 (i.e., the area on the lower wall portion 33 side that is forward of the conduit portion 50 in the bag body 26 when inflation is complete) overlapping the upper portion 73 above the conduit portion 50 (i.e., the area on the rear wall portion 37 side in the bag body 26 when inflation is complete). Therefore, when the inflation gas discharged from the inflator 17 flows into the bag body 26 through the conduit 50 and the communication holes 41, the inflation gas flowing into the bag body 26 from the communication holes 41 pushes up the lower rolled folded portion 77 and the upper rolled folded portion 76. The lower rolled folded portion 77, which is placed above the lower rolled folded portion 77, first unfolds and inflates while protruding forward and upward from the lap belt 10, and then the upper rolled folded portion 76 unfolds and inflates. Explaining the behavior of the bag body 26 in detail, as shown in Figures 9A and 9B, the lower rolled folded portion 77 first unfolds and inflates while allowing the inflation gas to flow into the bag body 26. However, because the lower rolled folded portion 77 is formed so as to be rolled toward the front wall 32 (the front panel 65), it is prevented from protruding forward too much. The front lower region 29 of the bag main body 26 folded by the lower rolled fold 77 inflates over the thighs MT of the occupant MP while protruding forward and upward, as shown in B of Fig. 9. Next, the upper rolled fold 76 inflates so as to protrude upward between the front lower region 29 and the upper body MU of the occupant MP (see B of Fig. 9). This upper rolled fold 76 is also formed so as to be rolled toward the front wall 32 (the front panel 65), and therefore is prevented from protruding excessively toward the occupant MP (upper body MU).That is, in the occupant protection device S of the embodiment, the front lower region (front lower end 26b side) of the bag main body 26 (front lower portion 29) inflates first while unfolding, and the rear upper region (upper end 26a side) of the bag main body 26 (upper portion 30) that is located in front of the upper body MU of the occupant MP upon completion of inflation is restricted from protruding forward away from the occupant MP by the front lower portion 29 that inflates first, so that the upper portion 30 protrudes upward and can inflate at a position in front of and close to the upper body MU of the occupant MP (see A and B in FIG. 10). Therefore, the inflated bag main body 26 can quickly cover the front side of the upper body MU of the occupant MP, and can quickly restrain the shoulders MS, head MH, etc. of the occupant MP.

[0029] Therefore, in the occupant protection device S of the embodiment, the airbag 25 that has completed inflation can quickly protect the upper body MU of the occupant MP.

[0030] In the occupant protection device S of the embodiment, the inflated airbag 25 (bag main body 26) is configured to quickly protect the upper body MU of the occupant MP, but the bag main body 26 is configured such that the bent portion 38 is disposed in the vertically intermediate portion of the rear wall portion 37 (the region that protects the thorax MB), and the upper restraining surface 44a (upper portion 37a) above the bent portion 38 protrudes toward the occupant MP (rearward) more than the lower restraining surface 44b (lower portion 37b) below the bent portion 38. Therefore, even when the airbag 25 is configured to quickly inflate at a position close to and in front of the upper body MU of the occupant MP, the inflating bag main body 26 can be prevented from immediately coming into contact with the occupant MP's thorax MB and from pressing against the thorax MB more than necessary, thereby softly restraining the upper body MU.

[0031] Furthermore, in the occupant protection device S of the embodiment, the bag body 26 is configured to be folded via a front-to-back shrink fold after a left-to-right shrink fold that reduces the left-to-right width dimension of the pre-folded bag 70, and the left-to-right shrink fold bag 72 is configured to be formed so that the left edge 70a and the right edge 70b of the pre-folded bag 70 overlap each other. Therefore, since the fully folded body 80 formed by folding the bag body 26 can be formed compactly in the left-to-right direction, even if the fully folded body 80 is positioned slightly offset left-to-right with respect to the seat 1 due to differences in the physiques of occupants seated in the seats, the influence of such misalignment can be suppressed, and the bag body 26 can be quickly inflated without being affected by the seat 1, etc. Note that if such a point is not taken into consideration, the pre-folded bag may be configured to be folded without undergoing a left-to-right shrink fold, or even when folding via a left-to-right shrink fold, the left and right edges of the pre-folded bag may be slightly folded so that they do not overlap each other.

[0032] In the occupant protection device S of the embodiment, the lap belt 10 of the seat belt 7 is used as a holder for holding the airbag 25, but the holder for holding the airbag is not limited to the lap belt. For example, a holder separate from the seat belt may be provided and the airbag may be held in this holder. In the occupant protection device S of the embodiment, the airbag 25 is held in the lap belt 10 of the seat belt 7. However, since the inflator 17 operates with a delay (approximately 5 ms) from the operation of the pretensioner mechanism of the seat belt 7, the airbag 25 can be inflated while the seat belt 7 stably maintains the occupant MP seated in the seat 1, and the airbag 25 and the seat belt 7 can stably protect the occupant MP.

[0033] Furthermore, in the occupant protection device S of the embodiment, the seat belt 7 and the inflator 17 are configured to be mounted on the seat 1. Therefore, even when the seat 1 is used in a state where it is moved relative to the vehicle by sliding it significantly forward and backward or rotating it, the occupant MP seated in the seat 1 can be adequately protected by the airbag 25. Of course, the occupant protection device of the present invention is not limited to a seat 1 configured as described above, and can also be mounted on a type of seat that restrains the occupant with a seat belt having a retractor provided on the vehicle body side. The inflator may also be configured to be attached to the vehicle body side. [Explanation of symbols]

[0034] 1...seat, 7...seat belt, 10...lap belt (retainer), 17...inflator, 25...airbag, 26...bag body, 32...front wall portion, 33...lower wall portion, 37...rear wall portion, 50...duct portion, 70...pre-folded bag, 72...left and right reduced folded bags, 73...upper portion, 73a...upper edge, 74...lower portion, 74a...lower edge, 76...upper roll-folded portion, 77...lower roll-folded portion, 80...completely folded body, MP...occupant, MU...upper body, S...occupant protection device.

Claims

1. It is configured to protect the occupant seated in the seat, The vehicle occupant protection device is configured to include an airbag, a holder that is disposed around the waist of the occupant and that stores and holds the folded airbag, and an inflator that supplies inflation gas to the airbag, The airbag, a bag body that is disposed to cover the front of the occupant when inflation is complete; a conduit portion connected to the inflator for allowing the inflation gas discharged from the inflator to flow into the bag body through a communication hole; With The bag body inflates while protruding forward and upward from the holder, and has an outer shape at the time of complete inflation that is a substantially triangular prism shape with an axial direction substantially aligned with the left-right direction, and is configured to include a front wall portion that is located on the front side away from the occupant at the time of complete inflation, and a rear wall portion and a lower wall portion that are located on the occupant side at the time of complete inflation, The bag body is held by the holder in a fully folded state in which the bag body is folded by front-to-rear contraction folding so as to reduce the width dimension in the front-to-rear direction from a state of a pre-folded bag in which the bag body is laid over the rear wall portion and the lower wall portion while being flattened over substantially the entire area of ​​the front wall portion, and a lower rolled fold portion formed by wrapping a lower portion of the pre-folded bag below the conduit portion from its lower edge toward the front wall portion, the lower portion being superimposed on an upper rolled fold portion formed by wrapping an upper portion of the pre-folded bag above the conduit portion from its upper edge toward the front wall portion.

2. The bag body is folded by being foldable through a front-rear shrinking fold after being foldable in a left-right shrinking fold so as to reduce the width dimension of the pre-folded bag in the left-right direction, 2. The passenger protection device according to claim 1, wherein the left and right shrink-folded bags are formed by overlapping the left and right edge sides of the pre-folded bag with each other.

Images