Airbag device

Abstract

To provide an airbag device which properly protects an occupant according to a situation and a body type of an occupant.SOLUTION: An airbag device 1 includes an airbag body part 10 which is expanded from a folded state by a gas flowing thereinto to protect an occupant of a vehicle. The airbag body part 10 has a shape variable area 30, which has an expansion amount smaller than that of a main expansion part 10a at the upper side and varies its deployment shape according to a state of the occupant, at the lower side which moves toward the side where a seat of the occupant is installed.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an airbag device. [Background technology]

[0002] Conventionally, there are airbag devices that are installed in vehicles such as automobiles to protect occupants from impacts when the vehicle collides. Patent Document 1 discloses a technique related to an airbag device that is installed in the steering wheel of a vehicle and has a recess in part of the airbag body that faces the floor of the vehicle. With this airbag device, the abdomen of the occupant is positioned in the recess in the airbag body when the airbag body is deployed, so that the load on the abdomen in particular is reduced. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2013-529577 Summary of the Invention [Problem to be solved by the invention]

[0004] In the airbag device described in Patent Document 1, the deployed shape of the airbag body is constant, and therefore the load on the occupant's chest can be reduced under certain conditions. However, under different conditions, for example, under conditions where the occupant's condition or physique has changed, there is a demand for appropriate measures to be taken when load reduction is more necessary or when load reduction is not necessary.

[0005] Therefore, an object of the present disclosure is to provide an airbag device that appropriately protects an occupant depending on the situation and physique of the occupant. [Means for solving the problem]

[0006] The airbag device according to the present disclosure includes an airbag main body that inflates from a folded state due to an inflow of gas to protect a vehicle occupant, and the airbag main body has a shape-variable region on the lower side facing the seat of the occupant that inflates to a smaller amount than the upper main inflation section and whose deployed shape changes depending on the condition of the occupant. Effect of the Invention

[0007] According to the present disclosure, it is possible to provide an airbag device that appropriately protects an occupant depending on the situation and physique of the occupant. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a passenger-side perspective view of an airbag main body according to an embodiment. [Diagram 2] FIG. 2 is a perspective view of an airbag body portion according to an embodiment, taken from the vehicle body side. [Diagram 3] FIG. 2 is a perspective view showing a shape of an airbag main body before installation in one embodiment. [Figure 4] 1 is a cross-sectional view of an airbag device according to an embodiment. [Diagram 5] 5A to 5C are diagrams illustrating the operation of the airbag device according to the embodiment. [Figure 6] 13 is a graph showing the results of an analysis of the load on the chest of a dummy. [Figure 7] 13 is a graph showing the results of an analysis of the load on the chest of a dummy. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, exemplary embodiments will be described with reference to the drawings. Here, elements having substantially the same functions and configurations are denoted by the same reference numerals to avoid repetitive explanations, and elements not directly related to the present disclosure are not shown.

[0010] FIG. 1 is a passenger-side perspective view of an airbag body 10 provided in an airbag device 1 (see FIG. 4) according to one embodiment. FIG. 2 is a vehicle-body-side perspective view of the airbag body 10. In the following drawings, X, Y, and Z directions are illustrated for reference. The X direction is generally along the straight-ahead direction of a vehicle such as an automobile in which the airbag device 1 is employed. The Y direction is a direction perpendicular to the XZ plane and generally along the vehicle width direction. The Z direction is a direction generally perpendicular to the XY plane, i.e., the floor surface on which a passenger seat 100 (see FIG. 5) is placed.

[0011] The airbag body 10 is normally stored in a folded state in, for example, the steering wheel of an automobile. When the vehicle collides, the airbag body 10 inflates and deploys due to the inflow of gas, thereby protecting the occupant from the impact of the collision. Note that Figs. 1 and 2 show the state of the airbag body 10 when deployed. Hereinafter, in this embodiment, the airbag device 1 will be described as being for the driver's seat, installed on the steering wheel 101 (see Fig. 5(b)) of an automobile. In other words, the object to be protected is the occupant sitting in the driver's seat. In this case, Fig. 1 corresponds to a view seen from the occupant sitting in the driver's seat. Meanwhile, Fig. 2 corresponds to a view seen from the steering wheel 101 side.

[0012] Fig. 3 is a perspective view showing the shape of the airbag body 10 before installation. For reference, Fig. 3 shows the deployed shape of the airbag body 10 before installation, in which gas is injected into the internal space and the airbag body 10 is inflated. Fig. 4 is a cross-sectional view of the airbag device 1 taken along the XZ plane passing through the center position in the Y direction, corresponding to the IV-IV cross section in Fig. 1.

[0013] The airbag device 1 includes an airbag body 10, an inflator 11, a retainer 12, and a bag plate 13.

[0014] The airbag body 10 is a bag formed of one or more base fabrics. In this embodiment, the airbag body 10 is formed into a bag shape as a whole by combining and joining two base fabrics, that is, a first panel 20 which is a base fabric on the occupant side and a second panel 21 which is a base fabric on the vehicle body side, by sewing, bonding, welding, or the like. The second panel 21 has two types of through holes: an attachment port 22 for attaching the inflator 11, and an exhaust port 23 for exhausting gas from the internal space of the airbag body 10 to the outside after inflation. A through hole such as the exhaust port 23 is sometimes called a vent hole.

[0015] First, referring to the pre-installation shape of the airbag main body 10 shown in FIG. 3, the airbag main body 10 includes a main inflatable portion 10a and a pair of rod-shaped inflatable portions, a first rod-shaped inflatable portion 10b and a second rod-shaped inflatable portion 10c.

[0016] The main inflation portion 10a is an inflation region located on the upper side in the Z direction of the airbag body portion 10. When the airbag body portion 10 is deployed, the main inflation portion 10a is expected to restrain the head, shoulders, or part of the chest of the occupant.

[0017] The first rod-shaped inflatable portion 10b and the second rod-shaped inflatable portion 10c are inflatable regions located on the lower side in the Z direction of the airbag body 10. The internal spaces of the first rod-shaped inflatable portion 10b and the second rod-shaped inflatable portion 10c are continuous with the main inflatable portion 10a, and extend downward in the Z direction from the main inflatable portion 10a when the airbag body 10 is in a deployed shape before installation. Here, downward in the Z direction refers to the direction toward the installation side of the occupant's seat 100. The first rod-shaped inflatable portion 10b and the second rod-shaped inflatable portion 10c face each other while being spaced apart from each other in the Y direction.

[0018] The airbag body 10 also has a connecting member 14 and an insertion and holding portion 10e.

[0019] The connecting member 14 is a strap (string-like member) having one end connected to the tip of the first rod-shaped inflatable portion 10b and the other end connected to the tip of the second rod-shaped inflatable portion 10c. In other words, the connecting member 14 connects the tip of the first rod-shaped inflatable portion 10b and the tip of the second rod-shaped inflatable portion 10c. In this embodiment, the connecting member 14 is a flat strap. When the airbag body 10 is in a deployed shape before installation, the connecting member 14 has slack.

[0020] The insertion and holding portion 10e is a tab (a plate-shaped portion) provided on a part of the main inflatable portion facing the space S between the first rod-shaped inflatable portion 10b and the second rod-shaped inflatable portion 10c. As shown in FIG. 3, the insertion and holding portion 10e may be provided as a part of the remaining margin remaining on the outer periphery when the first panel 20 and the second panel 21 are joined. The insertion and holding portion 10e has an insertion hole 10f through which the connecting material 14 is inserted. The insertion hole 10f is a hole that penetrates along the joining direction of the first panel 20 and the second panel 21. The insertion hole 10f has a shape that allows at least a part of the connecting material 14 in the folded state to be inserted therethrough. In this embodiment, the insertion hole 10f is formed in a slit shape having a length greater than the width of the connecting material 14.

[0021] The inflator 11 is a device that introduces gas (inflation gas) into the airbag main body 10. For example, the inflator 11 includes an igniter, a gas generating agent, and the like. In this case, the igniter burns the gas generating agent based on an electric signal that is generated when an electronic control unit (not shown) detects or predicts a car collision or the like, and thus gas is rapidly introduced into the airbag main body 10.

[0022] The retainer 12 is a frame for mounting the airbag body 10 and the inflator 11 to an installation portion on the vehicle side.

[0023] The bag plate 13 is a member that supports the retainer 12. The bag plate 13 may be a part of an installation portion on the vehicle side, for example, a part of the steering wheel 101 in this embodiment. The airbag device 1 may also be installed on the steering wheel 101 in a state where the airbag body 10, the inflator 11, and the retainer 12 are housed in a case (not shown). In this case, the bag plate 13 may be a part of the case.

[0024] Furthermore, the airbag device 1 includes a connecting member holding portion 15 that holds the connecting member 14 inserted through the insertion hole 10f provided in the insertion holding portion 10e. As shown in FIG. 2, the connecting member 14 is inserted through the insertion hole 10f with the direction from the first panel 20 side toward the second panel 21 side as the insertion direction. Since one end of the connecting member 14 is connected to the tip of the first rod-shaped inflatable portion 10b and the other end is connected to the tip of the second rod-shaped inflatable portion 10c, the connecting member 14 inserted through the insertion hole 10f becomes annular as a whole. Therefore, the connecting member holding portion 15 may be a rod-shaped or hook-shaped protruding portion that is installed on the bag plate 13 and hooks and holds a part of the annular connecting member 14 as shown in FIG. 4.

[0025] Next, the deployed shape of the airbag body 10 when the airbag device 1 is activated will be described with reference to Figs.

[0026] When gas is introduced from the inflator 11 into the airbag body 10, the main inflation section 10a inflates. In addition, the first rod-shaped inflation section 10b and the second rod-shaped inflation section 10c, to which gas is introduced through the respective communication ports 10g in the internal space of the airbag body 10, also inflate in accordance with the inflation of the main inflation section 10a. The connecting material 14 inserted through the insertion hole 10f is held by the connecting material holding section 15 provided on the vehicle body side before the airbag body 10 is deployed. Therefore, when gas is introduced and the airbag body 10 starts to inflate, the connecting material 14 inserted through the insertion hole 10f is pulled in the insertion direction. The insertion hole 10f is provided in a part of the main inflation section 10a facing the space S between the first rod-shaped inflation section 10b and the second rod-shaped inflation section 10c facing each other. Therefore, the respective tips of the first rod-shaped inflatable portion 10b and the second rod-shaped inflatable portion 10c are drawn toward the insertion hole 10f, and the first rod-shaped inflatable portion 10b and the second rod-shaped inflatable portion 10c inflate into a shape folded into the space S, as shown in Figures 1 and 2. As a result, the airbag body 10, which has a shape including a recess formed by the first rod-shaped inflatable portion 10b and the second rod-shaped inflatable portion 10c before installation, unfolds into a circular shape as a whole.

[0027] As a result of such inflation, a shape-variable region 30 is formed in a part of the airbag body 10 facing the occupant when deployed, as shown in Fig. 1 and Fig. 4. The shape-variable region 30 includes the first rod-shaped inflation portion 10b and the second rod-shaped inflation portion 10c inflated to a shape folded into the space S, and a lower part of the main inflation portion 10a continuous with the first rod-shaped inflation portion 10b and the second rod-shaped inflation portion 10c. A part of the occupant's body that is restrained by the shape-variable region 30 when the airbag body 10 deploys is assumed to be a part of the chest or the abdomen. The amount of inflation in the shape-variable region 30 is smaller than the amount of inflation in the main inflation portion 10a located above the part of the shape-variable region 30, because the part of the shape-variable region 30 is an area where the first rod-shaped inflation portion 10b and the second rod-shaped inflation portion 10c are folded into the space S.

[0028] Next, the operation of the airbag device 1 will be described.

[0029] FIG. 5 is a diagram for explaining an example of the operation of the airbag device 1 using a dummy D. FIG. 5 illustrates the restraining state of the dummy D when the airbag body 10 is deployed, assuming a frontal collision of the vehicle. FIG. 5(a) illustrates the restraining state of the dummy D when viewed from the front side of the vehicle. FIG. 5(b) illustrates the restraining state of the dummy D when viewed from the side of the vehicle. At this time, the dummy D is lifted up from the seat 100 due to the frontal collision of the vehicle, and is pressed against the airbag body 10 deployed from the steering wheel 101.

[0030] When the airbag main body 10 is deployed, the shape-variable region 30 is formed in the airbag main body 10 as described above. The amount of inflation of the shape-variable region 30 is smaller than that of the main inflation portion 10a located above it. Therefore, when the airbag main body 10 restrains the dummy D, it mainly receives the shoulders of the dummy D. In other words, the airbag main body 10 does not easily compress the chest (or abdomen) D1 of the dummy D.

[0031] 6 and 7 are graphs showing the results of an analysis of the load applied to the chest D1 of a dummy D due to restraint by the airbag main body 10. The dummy D used for the analysis is a THOR (Test Device for Human Occupant Restraint) dummy. As shown in FIG. 5, the dummy D includes displacement gauges installed at four locations, top, bottom, left and right, to measure the amount of displacement of the chest D1 due to restraint (hereinafter referred to as "chest displacement"). Of these, the first displacement gauge G UL The measurement point is set at the upper left position of the chest D1. UR The measurement point is set at the upper right position of the chest D1. LL The measurement point is set at the lower left position of the chest D1. LR The measurement point is set at the lower right position of the chest D1.

[0032] The graph shown in Figure 6(a) shows the displacement of the first displacement meter G ULThe graph in Fig. 6(b) shows the change in chest displacement [mm] against time [ms] after the collision obtained by the second displacement meter G UR The graph in Fig. 7(a) shows the change in chest displacement [mm] against the time [ms] after the collision obtained by the third displacement meter G LL The graph in Fig. 7(b) shows the change in chest displacement [mm] against the time [ms] after the collision obtained by the fourth displacement meter G LR The figure shows the change in chest displacement [mm] versus time [ms] after the collision, obtained by

[0033] In each graph, the value when the airbag device 1 according to this embodiment is adopted is indicated as "Airbag A". As a comparative example, the value when a conventional airbag device having a simple circular airbag body is adopted is indicated as "Airbag B". Furthermore, as a comparative example, the value when no airbag device is adopted is indicated as "No Airbag". Note that dummy D is wearing a seat belt in all cases.

[0034] With reference to these analysis results, there is a tendency for chest displacement to be large when restrained by the airbag body in the case of conventional airbag B. In contrast, it can be seen that the peak value of chest displacement in the case of airbag A of the present embodiment is lower than that in the case of airbag B, as indicated by the outlined arrows in each graph. In other words, by employing the airbag device 1 according to the present embodiment, there is a high possibility that the load on the occupant's chest can be reduced compared to the case of employing a conventional general airbag device.

[0035] In this embodiment, the shape-variable region 30 is formed by the first rod-shaped inflating portion 10b and the second rod-shaped inflating portion 10c inflated to a shape that is folded into the space S. The first rod-shaped inflating portion 10b and the second rod-shaped inflating portion 10c are inflating portions independent of each other while using the main inflating portion 10a as a reference. Therefore, when the airbag body portion 10 is deployed, the individual shapes of the first rod-shaped inflating portion 10b and the second rod-shaped inflating portion 10c are not always constant relative to the main inflating portion 10a. For example, depending on the condition of the occupant, such as the physique, the first rod-shaped inflating portion 10b may be pushed forward in the X direction more than the second rod-shaped inflating portion 10c, or the first rod-shaped inflating portion 10b may be folded into the space S by a larger amount than the second rod-shaped inflating portion 10c. In other words, the shape-variable region 30 changes its deployed shape depending on the condition of the occupant. Here, the condition of the occupant includes the condition of the occupant, the physique of the occupant, and the like. The occupant's condition includes the occupant's posture, which changes depending on the collision angle of the vehicle and the magnitude of the impact, etc. The occupant's physical constitution takes into account not only the body size but also age and gender differences.

[0036] Next, the effects of the airbag device 1 will be described.

[0037] The airbag device 1 according to this embodiment includes an airbag body 10 that inflates from a folded state with the inflow of gas to protect a vehicle occupant. The airbag body 10 has a shape variable region 30 on the lower side facing the seat 100 for the occupant, which has a smaller inflation amount than the upper main inflation section 10a and whose deployed shape changes depending on the state of the occupant.

[0038] According to this airbag device 1, the airbag body 10 has the shape-variable region 30 that has a smaller amount of inflation than the main inflation section 10a, so that the load on the occupant to be protected, particularly on the chest, can be reduced.

[0039] Furthermore, according to this airbag device 1, the shape-variable region 30 changes its deployed shape depending on the state of the occupant, so that the load on the occupant's chest can be reduced according to the condition, physique, etc. of the occupant.

[0040] In this way, according to this embodiment, it is possible to provide the airbag device 1 that appropriately protects the occupant depending on the situation and physique of the occupant.

[0041] In the airbag device 1, the shape-variable region 30 may include a first rod-shaped inflatable portion 10b and a second rod-shaped inflatable portion 10c, whose internal space is continuous with the main inflatable portion 10a and which serve as a pair of rod-shaped inflatable portions extending from the main inflatable portion 10a toward the installation side of the seat 100. The pair of rod-shaped inflatable portions may inflate into a shape that is folded into the space S between the opposing portions when the airbag body portion 10 is deployed.

[0042] According to this airbag device 1, the shape-variable region 30 can be easily provided in the airbag body 10. Furthermore, when the shape-variable region 30 is formed by such a pair of rod-shaped inflatable parts, the volume of the airbag body 10 does not exceed the volume of an airbag body used in a conventional airbag device installed in a similar installation target. Therefore, the inflator 11 employed in the airbag device 1 may be equivalent to an inflator employed in a conventional airbag device, which has the advantage that it is not necessary to employ a larger inflator.

[0043] In the airbag device 1, the airbag body 10 may have a connecting member 14 having one end connected to the tip of the first rod-shaped inflatable portion 10b, which is one of the rod-shaped inflatable portions, and the other end connected to the tip of the second rod-shaped inflatable portion 10c, which is the other rod-shaped inflatable portion. The airbag body 10 may have an insertion holding portion 10e having an insertion hole 10f through which the connecting member 14 is inserted, which is provided in a part of the main inflatable portion 10a facing the space S between the pair of rod-shaped inflatable portions facing each other. In this case, when the airbag body 10 is deployed, the connecting member 14 inserted through the insertion hole 10f may be pulled in the insertion direction so that the pair of rod-shaped inflatable portions are folded into the space S between the opposing portions.

[0044] According to this airbag device 1, the shape-variable region 30 is easily formed in the airbag body 10 in association with the inflation action caused by the introduction of gas, and as a result, the shape-variable region 30 can be stably formed.

[0045] Also, as a reference example, in an airbag device in which a tether (tether) provided inside pulls a part of the base material inward to form a recess (depression) in the airbag body, the shape of the inflatable portion located above the recess is likely to change before and after the recess is formed. In contrast, in the airbag device 1 according to this embodiment, the shape of the main inflatable portion 10a is stable and is unlikely to change between when the pair of rod-shaped inflatable portions are not folded and when they are folded to form the shape-variable region 30, as illustrated in Fig. 3. In other words, according to the airbag device 1, even if the shape-variable region 30 is formed in the airbag body 10, the function of the main inflatable portion 10a is unlikely to deteriorate.

[0046] The airbag device 1 according to this embodiment is not limited to being installed on the steering wheel 101, but may be adopted as an airbag device for a passenger seat installed on the instrument panel of an automobile, for example.

[0047] In addition, the embodiments can be modified or changed based on the above disclosure. Furthermore, all the components of the above embodiments and all the features described in the claims may be individually extracted and combined, unless they are mutually inconsistent. [Explanation of symbols]

[0048] 1 Airbag device 10 Airbag body 10a Main expansion section 10b First rod-shaped expansion portion 10c Second rod-shaped expansion section 10f Insertion hole 10e Insertion holding part 14 Connecting material 30 Shape-changing area S space

Claims

1. an airbag body that inflates from a folded state due to an inflow of gas to protect a vehicle occupant; the airbag body has a shape-variable region on a lower side facing the seat of the occupant, the shape-variable region having a smaller inflation amount than the upper main inflation portion, and the deployed shape of the shape-variable region changes depending on the state of the occupant, the shape-variable region includes a pair of rod-shaped inflatable portions whose internal space is continuous with the main inflatable portion and which extend from the main inflatable portion toward the installation side of the seat, The pair of rod-shaped inflatable portions inflate into a shape that is folded into the space between the opposing portions when the airbag body is deployed.

2. The airbag body portion is a connecting member having one end connected to a tip of one of the rod-shaped expansion portions and the other end connected to a tip of the other rod-shaped expansion portion; an insertion and holding portion provided in a part of the main expansion portion facing the space between the pair of rod-shaped expansion portions facing each other, the insertion and holding portion having an insertion hole through which the connecting material is inserted; 2. The airbag device according to claim 1, wherein when the airbag main body is deployed, the pair of rod-shaped inflation portions are folded into the space between the opposing portions by pulling the connecting material inserted through the insertion hole in the insertion direction.

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