Occupant protection device

Abstract

To provide an occupant protection device capable of suppressing compression of a protection target portion of an occupant by an airbag, even when a vehicle undergoes an oblique collision and the occupant moves obliquely forward.SOLUTION: An occupant protection device 10 comprises an airbag 30 which is provided on a lap belt portion 13 and includes: a bag main body portion 30a that inflates upon supply of inflation gas to receive an occupant M; and a conduit portion 30b that is connected to an inflator 24, guides the inflation gas discharged from the inflator 24 to the bag main body portion 30a to introduce the inflation gas into the bag main body portion 30a. A rear wall portion 30a1 opposed to the occupant M in the bag main body portion 30a at the time of inflation completion is provided with a recessed portion 30a1a. The recessed portion 30a1a is recessed forward and extends from a left end 30a1x to a right end 30a1y of the rear wall portion 30a1 so as to penetrate in the left-right direction.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to an occupant protection device that protects an occupant sitting on a vehicle seat.

Background Art

[0002] Conventionally, as an occupant protection device for protecting an occupant, a configuration in which a seat belt for restraining the occupant to the seat is provided is widely known. Further, Patent Document 1 describes a configuration in which an airbag is provided in a lap belt portion that restrains the waist of the occupant in the seat belt, and the airbag receives and protects the occupant.

[0003] Further, Patent Document 1 describes a configuration in which a concave portion that is recessed forward is provided in a rear wall portion facing the occupant in the airbag when inflation is completed. As a result, when the inflation of the airbag is completed, the portion of the occupant facing the concave portion is less likely to come into pressure contact with the airbag, so that the portion of the occupant facing the airbag is suppressed from being pressed by the airbag.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the concave portion described in Patent Document 1 does not extend from the left end portion to the right end portion of the rear wall portion of the airbag, and exists only near the center in the left-right direction of the rear wall portion. Therefore, when the vehicle collides obliquely and the occupant moves obliquely forward, there is a possibility that the concave portion is displaced left and right with respect to the protection target portion where it is desired to suppress the pressure by the airbag on the occupant. In that case, there is a possibility that the pressure on the protection target portion of the occupant by the airbag cannot be accurately suppressed.

[0006] Therefore, an object of the present invention is to provide an occupant protection device that can suppress the protected part of the occupant from being pressed by the airbag even when the vehicle is involved in an oblique collision and the occupant moves diagonally forward.

Means for Solving the Problems

[0007] A typical configuration of an occupant protection device according to the present invention for solving the above problems is an occupant protection device that protects an occupant sitting on a seat, and includes a seat belt having a lap belt portion configured to restrain the waist of the occupant sitting on the seat, an inflater that discharges inflation gas, and an airbag provided in the lap belt portion. The airbag includes a bag body portion that expands by being supplied with the inflation gas to receive the occupant, and a conduit portion connected to the inflater and guiding the inflation gas discharged from the inflater to the bag body portion to allow the inflation gas to flow into the bag body portion. In the rear wall portion of the bag body portion facing the occupant when inflation is completed, a concave portion that is recessed forward is provided, and the concave portion extends from the left end portion to the right end portion of the rear wall portion so as to penetrate in the left-right direction.

[0008] According to the present invention, in the occupant protection device, even when the vehicle is involved in an oblique collision and the occupant moves diagonally forward, it is possible to suppress the protected part of the occupant from being pressed by the airbag.

Brief Description of the Drawings

[0009]

Figure 1

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Figure 8

Mode for Carrying Out the Invention

[0010] First, the overall configuration of the occupant protection device 10 according to an embodiment of the present invention will be described with reference to the drawings. Note that the dimensions, materials, shapes, relative arrangements, etc. of the components described below are not intended to limit the scope of the present invention only to those, unless otherwise specifically described. Also, in the following description, the left-right direction means the left direction and the right direction of the seat 1 on which the occupant protection device 10 is mounted, specifically, the left direction and the right direction as seen from the occupant M sitting on the seat 1. The front-rear direction means the front direction and the rear direction of the seat 1, specifically, the front direction and the rear direction as seen from the occupant M sitting on the seat 1. The up-down direction means the upward and downward directions in the vertical direction.

[0011] FIG. 1 is a perspective view of the seat 1 on which the occupant protection device 10 is mounted. FIG. 2 is a left side view of the seat 1. FIG. 3 is a front view of the seat 1, and shows the occupant M sitting on the seat 1 and wearing the seat belt 11 and the inflated airbag 30 of the occupant protection device 10 with a two-dot chain line. FIG. 4 is a left side view of the seat 1 with the airbag 30 inflated, and shows the occupant M sitting on the seat 1 and wearing the seat belt 11 with a two-dot chain line.

[0012] As shown in FIGS. 1 to 4, the occupant protection device 10 is mounted on the seat 1 of the vehicle and protects the occupant M sitting on the seat 1. The occupant protection device 10 includes a seat belt 11, a bag assembly 29 including an airbag 30, and an inflater 24 that supplies inflation gas to the airbag 30. The seat 1 includes a backrest portion 2 and a seat portion 5.

[0013] The seat belt 11 is a belt-like member that restrains the occupant M to the seat 1. The seat belt 11 is configured to be extendable from a retractor mechanism 15 provided inside near the upper left edge of the backrest portion 2. The lower end portion of the seat belt 11 is a fixed end fixed to an anchor member 17 provided on the left side of the seat portion 5. Also, a tongue 20 is provided at an intermediate portion of the seat belt 11. The tongue 20 is fastened to a buckle 19 provided on the right side of the seat portion 5 of the seat 1. The state where the occupant M is seated on the seat 1 and the tongue 20 is fastened to the buckle 19 is the state where the occupant M is wearing the seat belt 11.

[0014] The seat belt 11 in the state of being worn by the occupant M extends from the tongue 20 toward the retractor mechanism 15 side, is disposed on the front side of the upper body MU of the occupant M, and has a shoulder belt portion 12 that is a portion for restraining the upper body MU of the occupant M, and a lap belt portion 13 that extends from the tongue 20 toward the anchor member 17 side, is disposed on the front side of the waist MW of the occupant M, and is a portion for restraining the waist MW. That is, the lap belt portion 13 is configured to restrain the waist MW of the occupant M. The occupant M can release the fastening state of the tongue 20 to the buckle 19 by pressing a release button (not shown) provided on the buckle 19 and remove the tongue 20 from the buckle 19.

[0015] The retractor mechanism 15 has a pretensioner mechanism 16 configured to stop the pulling out of the seat belt 11 in case of a sudden pulling out of the seat belt 11, and further to wind up the pulled-out seat belt 11 in case of a vehicle collision or the like. The pretensioner mechanism 16 rotates the shaft around which the seat belt 11 is wound by operating a built-in gas generator to instantaneously wind up the seat belt 11.

[0016] The inflator 24 is composed of an inflator main body 25 that discharges inflation gas and a pipe portion 26 that guides the inflation gas discharged from the inflator main body 25 to the airbag 30. The inflator main body 25 is attached to a seat frame 4 that supports the seat portion 5 of the seat 1. The pipe portion 26 extends from the inflator main body 25 and has a shape that is bent substantially in an L shape along the bottom surface to the side surface of the seat portion 5.

[0017] The bag assembly 29 is composed of an airbag 30 including a bag main body portion 30a and a conduit portion 30b, a bag connection portion 52 that connects the airbag 30 to the lap belt portion 13, and an airbag cover 59. The bag main body portion 30a is housed inside the airbag cover 59 in a folded state before inflation gas is supplied from the inflator 24. The conduit portion 30b of the airbag 30 is connected to the pipe portion 26 of the inflator 24, takes in the inflation gas discharged from the inflator 24, and guides it to the bag main body portion 30a. The base end portion 30b2 of the conduit portion 30b of the airbag 30 and the pipe portion 26 of the inflator 24 are connected by being fastened with a clamp 27. The detailed configuration of each member constituting the bag assembly 29 will be described later.

[0018] Next, the protection operation of the occupant M by the occupant protection device 10 will be described. First, when the vehicle collides, the pretensioner mechanism 16 of the winder mechanism 15 operates, and the seat belt 11 worn by the occupant M is wound up to stabilize the seating posture of the occupant M on the seat 1. As a result, the lap belt portion 13 of the seat belt 11 is drawn toward the tongue 20 side, and the shoulder belt portion 12 connected to the lap belt portion 13 is drawn toward the shoulder side of the occupant M.

[0019] Next, the inflator 24 operates, and the inflation gas is supplied from the inflator main body 25 to the bag main body portion 30a of the airbag 30 via the pipe portion 26 and the conduit portion 30b of the airbag 30. As a result, the bag main body portion 30a expands. Thereafter, the upper body MU of the occupant M who moves forward due to the impact of the vehicle collision is received by the bag main body portion 30a. In this way, the occupant protection device 10 protects the occupant M.

[0020] Next, each member constituting the airbag assembly 29 will be described. FIG. 5 is a cross-sectional view of the airbag assembly 29 cut along the A-A cross-section shown in FIG. 3. FIG. 6 is a perspective view of the airbag assembly 29 with the airbag 30 inflated, as viewed from below, and the airbag cover 59 is omitted.

[0021] As shown in FIGS. 5 and 6, the airbag 30 includes a bag main body portion 30a that expands by being supplied with the inflation gas and receives the occupant M, and a conduit portion 30b that is connected to the pipe portion 26 of the inflator 24 and guides the inflation gas discharged from the inflator 24 to the inlet 30a3a of the bag main body portion 30a to allow the inflation gas to flow into the bag main body portion 30a. The bag main body portion 30a and the conduit portion 30b are each formed of a base fabric for the bag, which is a woven fabric formed by plain-weaving a polyester fiber or the like, and are connected by being sewn together.

[0022] When the inflation is completed, the bag body portion 30a is arranged so as to face the occupant M directly in front of the occupant M, and contacts the upper body MU of the forward-moving occupant M to receive the upper body MU. It has a rear wall portion 30a1, a front wall portion 30a2 arranged on the front side opposite to the rear wall portion 30a1, a lower wall portion 30a3 arranged on the lower side and supported by the thigh portion MF of the occupant M, and a left wall portion 30a4 and a right wall portion 30a5 arranged on the left and right respectively. When viewed from the left-right direction, the bag body portion 30a at the completion of inflation forms a substantially triangular shape with the rear wall portion 30a1, the front wall portion 30a2, and the left wall portion 30a4 or the right wall portion 30a5 as each side, excluding the concave portion 30a1a of the rear wall portion 30a1 described later. Two inlets 30a3a, which are openings for allowing the inflation gas in the conduit portion 30b to flow in, are provided in the lower wall portion 30a3 of the bag body portion 30a.

[0023] Further, the rear wall portion 30a1 is provided with a concave portion 30a1a that is recessed forward and extends from the left end portion 30a1x to the right end portion 30a1y of the rear wall portion 30a1 so as to penetrate in the left-right direction. The concave portion 30a1a is formed by an inner wall 30a1a1 extending downward and forward and an inner wall 30a1a2 extending downward and backward, and forms a substantially V-shaped with an opening at the rear when viewed from the left-right direction. Also, the concave portion 30a1a is arranged below the vertical central portion 30a1z of the rear wall portion 30a1. Note that the concave portion 30a1a can be formed by cutting the base fabric for the bag before sewing into a shape capable of forming the concave portion 30a1a, or by providing a tether inside the bag body portion 30a.

[0024] The conduit portion 30b is a cylindrical member that is respectively connected to the pipe portion 26 of the inflator 24 and the bag body portion 30a and extends along the longitudinal direction of the lap belt portion 13. The conduit portion 30b has a communication port 30b1 that communicates with the inlet 30a3a of the bag body portion 30a. The inflation gas inside the conduit portion 30b flows into the inside of the bag body portion 30a via the communication port 30b1 and the inlet 30a3a.

[0025] The bag connecting portion 52 is a tubular member formed of the same material as the base fabric for the bag that forms the airbag 30, and connects the airbag 30 to the lap belt portion 13. The upper surface of the bag connecting portion 52 and the lower surface of the conduit portion 30b of the airbag 30 are stitched and connected. The space inside the tube of the bag connecting portion 52 serves as a belt insertion portion 52a through which the lap belt portion 13 is inserted. When the lap belt portion 13 is inserted through the belt insertion portion 52a, the airbag 30 is connected to the lap belt portion 13 via the bag connecting portion 52.

[0026] The airbag cover 59 is a tubular member attached to the lap belt portion 13, and houses the entire bag body portion 30a of the airbag 30 in the folded state, a part of the conduit portion 30b, the bag connecting portion 52, and a part of the lap belt portion 13 inside the tube. When the bag body portion 30a expands, the airbag cover 59 receives pressure from the bag body portion 30a and breaks to form an opening, and the bag body portion 30a is fed out through this opening.

[0027] Next, the protection operation of the occupant protection device 10 when the vehicle undergoes an oblique collision will be described with reference to FIGS. 7 and 8. FIG. 7A is a schematic diagram showing the positional relationship between the occupant M and the airbag 30 when the vehicle undergoes an oblique collision, and shows a view of the occupant M and the airbag 30 as seen from above. FIG. 8 is a schematic diagram showing the positional relationship between the occupant M and the airbag 30 when the vehicle collides, and shows a view of the occupant M and the airbag 30 as seen from the left side.

[0028] As shown in Fig. 7A, when the vehicle is involved in an oblique collision, the occupant M does not move straight forward but moves forward and to the right or left. In Fig. 7A, the state where the occupant M moves forward and to the right is shown. In this case, if the recess 30a1a of the rear wall portion 30a1 of the airbag main body portion 30a does not extend from the left end portion 30a1x to the right end portion 30a1y of the rear wall portion 30a1 and is partially arranged near the center in the left-right direction, there is a risk that the recess 30a1a will be displaced left and right with respect to the protected parts such as the lower abdomen and chest of the occupant M. In that case, the protected part of the occupant M may not fit well into the recess 30a1a and the protected part may be pressed by the airbag main body portion 30a.

[0029] On the other hand, in the occupant protection device 10 of the present embodiment, the recess 30a1a of the rear wall portion 30a1 of the airbag main body portion 30a extends from the left end portion 30a1x to the right end portion 30a1y of the rear wall portion 30a1 so as to penetrate in the left-right direction. Therefore, even when the vehicle is involved in an oblique collision and the occupant M moves obliquely forward, it is possible to prevent the recess 30a1a from being displaced left and right with respect to the protected part of the occupant M. As a result, the protected part of the occupant M is likely to fit into the recess 30a1a, and it is possible to suppress the protected part from being pressed by the airbag main body portion 30a. This configuration is particularly effective for an occupant M such as a pregnant woman who has a large abdominal circumference and requires protection of the lower abdomen. In addition, the configuration of the present embodiment is not limited to the case where the vehicle is involved in an oblique collision. As shown in Fig. 7B, even when the vehicle is involved in a frontal collision with the center position of the airbag main body portion 30a in the left-right direction being displaced left and right with respect to the occupant M and the airbag 30 is inflated, the same effect can be obtained.

[0030] Further, since the airbag main body portion 30a of the present embodiment has the recess 30a1a, the volume of the portion into which the inflation gas flows in the airbag main body portion 30a is smaller than that of a configuration without the recess 30a1a or a configuration in which the recess 30a1a is partially arranged near the center in the left-right direction of the rear wall portion 30a1. Therefore, according to the occupant protection device 10 of the present embodiment, since the time from the start to the completion of the inflation of the airbag main body portion 30a can be shortened, the occupant M can be protected more safely.

[0031] Further, the recess 30a1a is disposed below the vertical center portion 30a1z in the rear wall portion 30a1. Therefore, it becomes easier to accurately protect the lower abdomen and chest, which are the parts of the occupant M to be protected by the recess 30a1a of the present embodiment. That is, when the vehicle collides, as shown in FIG. 8, the occupant M is likely to assume a forward-leaning posture when moving forward. Therefore, by arranging the recess 30a1a in this manner, the lower abdomen of the occupant M is likely to fit into the recess 30a1a before the occupant M assumes a forward-leaning posture, and the chest is likely to fit into the recess 30a1a after assuming a forward-leaning posture. Therefore, it becomes easier to accurately protect the lower abdomen and chest of the occupant M, which are the parts to be protected. When the airbag 30 is provided in the lap belt portion 13, since the parts of the occupant M that are likely to be pressed by the airbag 30 are the lower abdomen and chest, the need to suppress the pressing of these parts is high. However, for example, when setting the neck of the occupant M as a part to be protected by the recess 30a1a, the recess 30a1a may be arranged above the central portion 30a1z of the rear wall portion 30a1 in the vertical direction.

[0032] In the present embodiment, the recess 30a1a is formed by the inner wall 30a1a1 and the inner wall 30a1a2, and has been described as having a substantially V-shaped configuration with an opening at the rear when viewed from the left-right direction. However, the present invention is not limited to this. The recess 30a1a may have other shapes as long as it extends from the left end portion 30a1x to the right end portion 30a1y of the rear wall portion 30a1 so as to penetrate in the left-right direction. For example, even if the inner wall 30a1a1 and the inner wall 30a1a2 are formed as a single curved surface and the recess 30a1a has an arc shape when viewed from the left-right direction, the same effects as described above can be obtained.

[0033] Also, in this embodiment, although the occupant protection device 10 has been described by exemplifying a so-called three-point seat belt 11 including a shoulder belt portion 12 and a lap belt portion 13, the present invention is not limited to this. That is, even if the present invention is applied to a so-called two-point seat belt 11 including a lap belt portion 13 without a shoulder belt portion 12, the same effects as described above can be obtained.

Explanation of Reference Numerals

[0034] 1... Seat, 10... Occupant protection device, 11... Seat belt, 13... Lap belt portion, 15... Retractor mechanism, 24... Inflator, 30... Airbag, 30a... Bag main body portion, 30a1... Rear wall portion, 30a1a... Recess, 30a1x... Left end portion, 30a1y... Right end portion, 30a1z... Central portion, 30b... Duct portion, M... Occupant, MW... Waist

Claims

1. An occupant protection device for protecting an occupant sitting on a seat, comprising a seat belt having a lap belt portion configured to restrain the waist of the occupant sitting on the seat, an inflater for discharging inflation gas, an airbag provided in the lap belt portion, the airbag having a bag body portion that inflates by being supplied with the inflation gas to receive the occupant, and a conduit portion connected to the inflater and guiding the inflation gas discharged from the inflater to the bag body portion to allow the inflation gas to flow into the bag body portion, and being provided with In a rear wall portion facing the occupant in the bag body portion at the time of inflation completion, there is provided a concave portion recessed forward, the concave portion extending from the left end portion to the right end portion of the rear wall portion so as to penetrate in the left - right direction. The occupant protection device is characterized by this.

2. The occupant protection device according to claim 1, wherein the concave portion is disposed below a central portion in the vertical direction of the rear wall portion.

3. comprising a winding mechanism capable of winding the seat belt, The occupant protection device according to claim 1, wherein the inflater and the winding mechanism are mounted on the seat.

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