Occupant protection device

Abstract

An occupant protection device (10) is provided with: a seat belt (11) having a belt section (13); an inflator (24) that releases the inflation gas; and an airbag (30) provided to the belt section (13) and having an airbag body section (30a) that is inflated by being supplied with the inflation gas and that holds an occupant, and a duct section (30b) that is connected to the inflator (24) and that guides the inflation gas released from the inflator (24) to the airbag body section (30a). In the airbag body section (30a) after inflation, a rear wall section (30a1) facing the occupant (M) is provided with a recessed section (30a1a) that is recessed forward and extends from a left end section (30a1x) to a right end section (30a1y) of the rear wall section (30a1) so as to pass through the rear wall section (30a1) in the left-right direction.

Description

Technical Field

[0001] The present invention relates to an occupant protection device for protecting an occupant sitting on a seat of a vehicle. Background Art

[0002] At present, as an occupant protection device for protecting an occupant, a structure of a seat belt for restraining an occupant on a seat is widely known. In addition, Patent Document 1 discloses a structure in which an airbag is provided at a waist belt portion of the seat belt for restraining the occupant's waist, and the airbag is used to receive and protect the occupant.

[0003] In addition, the specification of U.S. Patent Application Publication No. 2019 / 0299899 describes a structure in which a concave portion that is recessed toward the front side is provided on the rear wall portion of the airbag that is opposite to the occupant when the airbag is fully inflated. As a result, the portion of the occupant that is opposite to the concave portion is difficult to be pressed against the airbag when the airbag is fully inflated, thereby preventing the portion of the occupant that is opposite to the concave portion from being pressed against the airbag.

[0004] However, the recess described in the specification of U.S. Patent Application Publication No. 2019 / 0299899 does not extend from the left end to the right end of the rear wall of the airbag, but only exists near the center of the rear wall in the left-right direction. Therefore, in the case where the vehicle is tilted and the occupant moves diagonally forward, the recess may be offset in the left-right direction relative to the occupant's protected part that is to be suppressed from being compressed by the airbag. In this case, it may not be possible to reliably suppress the occupant's protected part from being compressed by the airbag. Summary of the invention

[0005] An object of the present invention is to provide an occupant protection device capable of preventing a protected part of the occupant from being pressed by an airbag even when the occupant moves diagonally forward due to an oblique collision of a vehicle.

[0006] A typical structure of the occupant protection device according to the present invention is as follows.

[0007] The occupant protection system has the following components:

[0008] A seat belt having a lap belt portion configured to restrain the waist of an occupant seated on the seat;

[0009] an inflator that releases inflation gas; and

[0010] An airbag is provided at the waist belt portion and comprises an airbag main body portion and a duct portion, wherein the airbag main body portion is inflated and supports an occupant by being supplied with the inflation gas, and the duct portion is connected to the inflator to guide the inflation gas released from the inflator to the airbag main body portion so that the inflation gas flows into the airbag main body portion, wherein:

[0011] In the airbag main body portion when inflation is complete, a recessed portion is provided in a rear wall portion facing the occupant, the recessed portion is recessed forward, and extends from a left end portion to a right end portion of the rear wall portion so as to penetrate in the left-right direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a perspective view of a seat equipped with an occupant protection device.

[0013] Figure 2 This is a left side view of the seat.

[0014] Figure 3 This is the front view of the seat.

[0015] Figure 4 It is a left side view of the seat when the air bag is inflated.

[0016] Figure 5 Yes Figure 3 The cross-sectional view of the airbag assembly is shown along the line AA.

[0017] Figure 6 This is a perspective view of the airbag assembly when the airbag is inflated, as seen from below.

[0018] Figure 7 A. Figure 7 B is a schematic diagram showing the positional relationship between the occupant and the airbag in the case of a frontal collision of the vehicle in a state where the airbag is arranged offset in the left-right direction relative to the occupant when the vehicle is tilted and collided.

[0019] Figure 8 This is a left side view showing the positional relationship between the occupant and the airbag during a vehicle collision. DETAILED DESCRIPTION

[0020] The embodiments of the present invention are described below with reference to the corresponding drawings. However, the present invention is not limited to the embodiments disclosed herein. All changes within the scope of the technical solution and its equivalent scope are included in the scope of the present invention.

[0021] Below, first, the overall structure of the occupant protection device 10 involved in one embodiment of the present invention is described with reference to the accompanying drawings. In addition, as long as the dimensions, materials, shapes, relative arrangements, etc. of the structural components described below are not specifically described, the scope of the present invention is not limited to these. In addition, in the following description, the left-right direction indicates the left and right sides of the seat 1 equipped with the occupant protection device 10, specifically, the left and right sides observed from the occupant M sitting on the seat 1. The front-to-back direction indicates the front and rear of the seat 1, specifically, the front and rear observed from the occupant M sitting on the seat 1. The up-down direction indicates the upper and lower sides in the vertical direction.

[0022] Figure 1 It is a perspective view of the seat 1 on which the occupant protection device 10 is mounted. Figure 2 It is a left side view of the seat 1. Figure 3 It is a front view of the seat 1 , and the occupant M sitting on the seat 1 and wearing the seat belt 11 and the airbag 30 of the occupant protection device 10 in an inflated state are shown by two-dot chain lines. Figure 4 It is a left side view of the seat 1 in a state where the airbag 30 is inflated, and the occupant M sitting on the seat 1 and wearing the seat belt 11 is indicated by two-dot chain lines.

[0023] like Figure 1 to Figure 4 As shown, the occupant protection device 10 is mounted on a seat 1 of a vehicle to protect an occupant M sitting on the seat 1. The occupant protection device 10 includes a seat belt 11, an airbag assembly 29 having an airbag 30, and an inflator 24 for supplying inflation gas to the airbag 30. The seat 1 includes a backrest portion 2 and a seat portion 5.

[0024] The seat belt 11 is a belt-shaped member that restrains the occupant M to the seat 1. The seat belt 11 is configured to be able to be drawn out from a reel-up mechanism 15 provided inside near the left upper edge of the backrest portion 2. The lower end 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. In addition, a tongue 20 is provided in the middle 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 in which the occupant M sits on the seat 1 and the tongue 20 is fastened to the buckle 19 is the state in which the seat belt 11 is worn by the occupant M.

[0025] The seat belt 11 in a state of being worn by the occupant M includes: a shoulder belt portion 12 extending from the tongue 20 toward the take-up mechanism 15, disposed on the front surface side of the upper body MU of the occupant M, and being a portion for restraining the upper body MU of the occupant M; and a lap belt portion 13 extending from the tongue 20 toward the anchor member 17, disposed on the front surface side of the waist MW of the occupant M, and being 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. In addition, the occupant M can release the fastening state of the tongue 20 with respect to the buckle 19 by pressing a release button (not shown) provided on the buckle 19, thereby removing the tongue 20 from the buckle 19.

[0026] The reeling mechanism 15 includes a pretensioning mechanism 16 configured to stop the seat belt 11 from being reeled out rapidly and to reel in the reeled seat belt 11 if a vehicle collision or the like further occurs. The pretensioning mechanism 16 rotates the shaft around which the seat belt 11 is reeled in by operating a built-in gas generator, thereby reeling in the seat belt 11 in an instant.

[0027] The inflator 24 is composed of an inflator body 25 that releases inflation gas, and a pipe 26 that guides the inflation gas released from the inflator body 25 to the airbag 30. The inflator body 25 is attached to the seat frame 4 that supports the seat 5 of the seat 1. The pipe 26 is provided so as to extend from the inflator body 25 and bend in a substantially L-shaped shape from the bottom surface of the seat 5 along the side surface.

[0028] The airbag assembly 29 is composed of the following components: an airbag 30 having an airbag main body 30a and a duct portion 30b; an airbag connecting portion 52 connecting the airbag 30 to the waist belt portion 13; and an airbag cover 59. The airbag main body 30a is accommodated in the airbag cover 59 in a folded state before the inflation gas is supplied from the inflator 24. The duct portion 30b of the airbag 30 is connected to the tube portion 26 of the inflator 24, and takes in the inflation gas released from the inflator 24 and guides it to the airbag main body 30a. The base end portion 30b2 of the duct portion 30b of the airbag 30 and the tube portion 26 of the inflator 24 are connected by fastening with a clamp 27. The detailed structure of each component constituting the airbag assembly 29 will be described later.

[0029] Next, the protection operation of the occupant M by the occupant protection device 10 will be described. First, when the vehicle collides, the pretensioner 16 of the reeling mechanism 15 is activated to reel in the seat belt 11 worn by the occupant M in order to stabilize the sitting posture of the occupant M on the seat 1. As a result, the lap belt portion 13 of the seat belt 11 is pulled toward the tongue 20, and the shoulder belt portion 12 connected to the lap belt portion 13 is pulled toward the shoulder of the occupant M.

[0030] Next, the inflator 24 operates, and the inflation gas is supplied from the inflator body 25 to the airbag body 30a of the airbag 30 via the tube 26 and the conduit 30b of the airbag 30. As a result, the airbag body 30a is inflated. Then, the upper body MU of the occupant M, which moves forward due to the impact of the vehicle collision, is received by the airbag body 30a. As a result, the occupant M is protected by the occupant protection device 10.

[0031] Next, each member constituting the airbag assembly 29 will be described. Figure 5 So Figure 3 The illustrated diagram is a cross-sectional view of the airbag assembly 29 taken along the line AA. Figure 6 This is a perspective view of the airbag assembly 29 in a state where the airbag 30 is inflated, as seen from below, and the airbag cover 59 is omitted.

[0032] like Figure 5 , Figure 6As shown in FIG. 1 , the airbag 30 is composed of the following components: an airbag body 30a, which is inflated by supplying inflation gas and supports the occupant M; and a duct 30b, which is connected to the tube 26 of the inflator 24, guides the inflation gas released from the inflator 24 to the inlet 30a3a of the airbag body 30a and allows the inflation gas to flow into the airbag body 30a. The airbag body 30a and the duct 30b are respectively formed of a base fabric for the airbag, which is a woven fabric formed by plain weaving polyester fibers, and are connected by sewing.

[0033] The airbag main body 30a when fully inflated includes: a rear wall 30a1, which is arranged in front of the occupant M to face the occupant M and contacts the upper body MU of the occupant M moving forward to support the upper body MU; a front wall 30a2, which is arranged on the opposite front side of the rear wall 30a1; a lower wall 30a3, which is arranged on the lower side and supports the thigh MF of the occupant M; and a left wall 30a4 and a right wall 30a5, which are arranged on the left and right sides, respectively. When viewed from the left and right directions, the airbag main body 30a when fully inflated forms an approximately triangular shape in which the rear wall 30a1, the front wall 30a2, and the left wall 30a4 or the right wall 30a5 are each set as one side, except for the concave portion 30a1a of the rear wall 30a1 described later. The lower wall portion 30a3 of the airbag body portion 30a is provided with two inlet ports 30a3a as openings for allowing the inflation gas in the duct portion 30b to flow in.

[0034] In addition, the rear wall portion 30a1 is provided with a recessed portion 30a1a which extends from the left end portion 30a1x of the rear wall portion 30a1 to the right end portion 30a1y in a manner that is recessed toward the front side and penetrates in the left-right direction. The recessed portion 30a1a is formed by an inner wall 30a1a1 extending downward and forward, and an inner wall 30a1a2 extending downward and rearward, and is formed into an approximately V-shaped shape with the rear portion being an opening when viewed from the left-right direction. In addition, the recessed portion 30a1a is arranged below the central portion 30a1z in the vertical direction of the rear wall portion 30a1. In addition, the recessed portion 30a1a can be formed by cutting the base fabric for the airbag before sewing into a shape that can form the recessed portion 30a1a and providing a tie inside the airbag main body portion 30a.

[0035] The duct portion 30b is a cylindrical member connected to the tube portion 26 of the inflator 24 and the airbag main body portion 30a, respectively, and extending in the longitudinal direction of the waist belt portion 13. The duct portion 30b has a communication port 30b1 that communicates with the inlet 30a3a of the airbag main body portion 30a. The inflation gas inside the duct portion 30b flows into the inside of the airbag main body portion 30a through the communication port 30b1 and the inlet 30a3a.

[0036] The airbag connecting portion 52 is a tubular member formed of the same material as the base fabric for forming the airbag 30, and connects the airbag 30 to the lap belt portion 13. The upper surface of the airbag connecting portion 52 and the lower surface of the duct portion 30b of the airbag 30 are sewn and connected. The space inside the tube of the airbag connecting portion 52 becomes a safety belt insertion portion 52a for inserting the lap belt portion 13. The lap belt portion 13 is inserted into the safety belt insertion portion 52a, and the airbag 30 is connected to the lap belt portion 13 via the airbag connecting portion 52.

[0037] The airbag cover 59 is a cylindrical member mounted on the waist belt portion 13. The airbag cover 59 accommodates the entire airbag body portion 30a of the folded airbag 30, a portion of the duct portion 30b, the airbag connecting portion 52, and a portion of the waist belt portion 13. When the airbag body portion 30a is inflated, the airbag cover 59 is ruptured by the pressure from the airbag body portion 30a, and an opening is formed, so that the airbag body portion 30a is led out from the opening.

[0038] Next, use Figure 7 A. Figure 7 B. Figure 8 The protection operation of the occupant protection device 10 when the vehicle is in an oblique collision will be described. Figure 7 A is a schematic diagram showing the positional relationship between the occupant M and the airbag 30 in the case of an oblique collision of the vehicle, and shows a state where the occupant M and the airbag 30 are viewed from above. Figure 8 1 is a schematic diagram showing the positional relationship between the occupant M and the airbag 30 in the event of a vehicle collision, and shows a state where the occupant M and the airbag 30 are viewed from the left side.

[0039] like Figure 7 As shown in A, in the case of a tilted collision of the vehicle, the occupant M does not move straight forward, but moves forward and to the right or left. Figure 7 A shows a situation where the occupant M moves forward and to the right. In this case, if the recessed portion 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, the recessed portion 30a1a may be arranged offset in the left-right direction with respect to the protected part such as the lower abdomen and chest of the occupant M. In this case, the protected part of the occupant M may not be smoothly accommodated in the recessed portion 30a1a, and the protected part may be compressed by the airbag main body portion 30a.

[0040] In contrast, 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 in a manner that is through in the left-right direction. Therefore, even in the case where the vehicle tilts and collides so that the occupant M moves diagonally forward, the recess 30a1a can be prevented from being offset in the left-right direction relative to the protected part of the occupant M. As a result, the protected part of the occupant M can be easily accommodated in the recess 30a1a, and the protected part can be suppressed from being compressed by the airbag main body portion 30a. This structure is particularly effective for occupants M such as pregnant women who have a large waist circumference and need to protect their lower abdomen. In addition, the structure of the present embodiment is not only effective in the case of a tilted collision of the vehicle, such as Figure 7 As shown in FIG. 2B , when the vehicle collides head-on and the airbag 30 is inflated in a state where the center position of the airbag main body 30 a in the left-right direction is offset relative to the occupant M, the same effect is achieved.

[0041] In addition, the airbag main body 30a of the present embodiment has the recessed portion 30a1a, so the volume of the portion of the airbag main body 30a into which the inflation gas flows is reduced compared to a structure without the recessed portion 30a1a or a structure in which the recessed portion 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, the time from the start of inflation of the airbag main body 30a to the completion of inflation can be shortened, so the occupant M can be protected more safely.

[0042] In addition, the recessed portion 30a1a is arranged below the central portion 30a1z of the rear wall portion 30a1 in the vertical direction. Therefore, the recessed portion 30a1a of the present embodiment can be used to reliably protect the lower abdomen and chest of the occupant M. That is, in the event of a vehicle collision, Figure 8 As shown, the occupant M tends to be in a forward leaning posture when moving forward. Therefore, by setting the recess 30a1a in this configuration, it is easy to store the lower abdomen of the occupant M in the recess 30a1a before the occupant M becomes in a forward leaning posture, and it is easy to store the chest in the recess 30a1a after the occupant M becomes in a forward leaning posture. Therefore, it is easy to reliably protect the lower abdomen and chest of the occupant M as the protection target parts. In addition, in the case where the airbag 30 is provided in the waist belt portion 13, the parts of the occupant M that are easily compressed by the airbag 30 are the lower abdomen and the chest, so it is necessary to suppress the compression of the above parts. However, for example, in the case where the neck of the occupant M is set as the protection target part of the recess 30a1a, it is possible to form a structure in which the recess 30a1a is configured to be higher than the central part 30a1z of the rear wall portion 30a1 in the vertical direction.

[0043] In addition, in the present embodiment, the following structure is described, that is, the recessed portion 30a1a is formed by the inner wall 30a1a1 and the inner wall 30a1a2, and is formed into a nearly V-shaped shape with the rear portion being an opening when viewed from the left and right directions. However, the present invention is not limited to this, and the recessed portion 30a1a may also be in other shapes if the recessed portion 30a1a extends from the left end portion 30a1x to the right end portion 30a1y of the rear wall portion 30a1 in a manner that penetrates in the left and right directions. For example, even if the structure is formed in which the inner wall 30a1a1 and the inner wall 30a1a2 are set as a single curved surface and the recessed portion 30a1a is formed into an arc shape when viewed from the left and right directions, the above-mentioned effect can be obtained.

[0044] In addition, in the present embodiment, the occupant protection device 10 is described by taking as an example a so-called three-point seat belt 11 in which the seat belt 11 has the shoulder belt portion 12 and the lap belt portion 13, but the present invention is not limited thereto. That is, even if the present invention is applied to a so-called two-point seat belt 11 in which the seat belt 11 does not have the shoulder belt portion 12 but has the lap belt portion 13, the above-mentioned effects can be obtained.

Claims

1. An occupant protection device (10), wherein: The occupant protection device (10) comprises the following components: A seat belt (11) having a waist belt portion (13) configured to restrain the waist (MW) of an occupant (M) sitting on the seat (1); an inflator (24) that releases inflation gas; and The airbag (30) is provided at the waist belt portion (13) and comprises an airbag main body portion (30a) and a duct portion (30b). The airbag main body portion (30a) is inflated and supports an occupant by being supplied with the inflation gas. The duct portion (30b) is connected to the inflator (24) and guides the inflation gas released from the inflator (24) to the airbag main body portion (30a), so that the inflation gas flows into the airbag main body portion (30a). In the airbag main body (30a) when inflation is complete, a recess (30a1a) is provided in the rear wall (30a1) opposite to the occupant (M), the recess (30a1a) being recessed toward the front side and extending from the left end (30a1x) to the right end (30a1y) of the rear wall (30a1) in a penetrating manner in the left-right direction.

2. The occupant protection device (10) according to claim 1, wherein: The recessed portion (30a1a) is arranged below a central portion (30a1z) of the rear wall portion (30a1) in a vertical direction.

3. The occupant protection device (10) according to claim 1, wherein: The occupant protection device (10) further comprises a reeling mechanism (15) capable of reeling the seat belt (11), and the inflator (24) and the reeling mechanism (15) are mounted on the seat (1).

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