JP7715076B2 - Occupant protection devices - Google Patents

Description

The present invention relates to an occupant protection device configured to protect an occupant seated in a seat.

Conventional occupant protection devices have been configured so that an inflator, which supplies inflation gas to an airbag folded and stored around the occupant's waist, is located in the area on the lower rear side of the seat where the occupant sits (see, for example, Patent Document 1). Specifically, in conventional occupant protection devices, the inflator is generally cylindrical and includes an inflator main body located on the lower rear side of the seat with its axial direction generally aligned with the left-right direction, and a connecting pipe portion that extends and bends from the inflator main body and connects to the airbag on the side of the seat.

JP 2020-66425 A

In this conventional occupant protection device, the connecting pipe extending from the inflator body is bent and connected to the airbag at a position to the side of the seat. Therefore, when a large impact force acts from either the left or right side, such as when a vehicle enters from the side, the connecting pipe can become deformed. If the connecting pipe becomes significantly deformed, inflation gas cannot be smoothly supplied to the airbag in the event of a secondary collision after the side impact force, preventing the airbag from inflating smoothly. Therefore, there is room for improvement in preventing this type of deformation from occurring.

The present invention aims to solve the above-mentioned problems by providing an occupant protection device that can smoothly inflate an airbag even if a secondary collision occurs after a side impact force.

The occupant protection device according to the present invention is configured to protect an occupant seated in a seat,
an airbag configured to be inflatable in a bag shape so as to cover the front of the occupant and to be held in a folded state by a holding belt part that is wrapped around the waist of the occupant;
an inflator that supplies inflation gas to the airbag;
An occupant protection device having a configuration comprising:
The inflator is
an inflator body having a generally cylindrical shape and disposed in a region below the rear surface of the seat portion of the seat with its axial direction generally aligned with the left-right direction;
a connecting pipe portion that is bent while extending from the inflator body and is disposed in a side area of the seat portion, and that connects the inflator body and the airbag;
The device is configured to include:
The connecting pipe portion is configured to have a base side portion that is on the inflator main body side, and a tip side portion that is arranged to intersect with the base side portion and is on the airbag side, and is characterized in that the tip side portion is supported by a support member so as to restrict the tip side portion from approaching the seat side when an external force acts on the seat side from the left or right side.

In the occupant protection device of the present invention, the connecting pipe section connecting the inflator body and the airbag is configured to be bent while extending from the inflator body, but the tip section on the airbag side is supported by a support member. Therefore, even if a large impact force acts from either the left or right side, such as when a vehicle enters from the side, the connecting pipe section is prevented from deforming from the bent section, bringing the tip section closer to the seat. As a result, when the inflator body is activated in the event of a secondary collision after a side impact force, inflation gas discharged from the inflator body can flow smoothly into the airbag via the connecting pipe section, allowing the airbag to inflate smoothly.

Therefore, with the occupant protection device of the present invention, the airbag can be smoothly inflated even if a secondary collision occurs after a side impact force is applied.

Specifically, one example of a support member is one that is configured to straddle the bent portion of the connecting pipe section and connect the base portion and tip portion, or the support member may be configured to protrude from the side of the seat frame.

1 is a perspective view of a seat equipped with an occupant protection device according to an embodiment of the present invention; FIG. 2 is a side view of the seat of FIG. 1; FIG. 2 is a front view of the seat of FIG. 1, showing the seat belt fastened; 2 is a partially enlarged rear view showing the lower end region of the seat portion of the seat of FIG. 1; FIG. 2 is a partially enlarged cross-sectional view showing the vicinity of an inflator arrangement position in the occupant protection device of the embodiment. FIG. 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; FIG. 7 is a schematic longitudinal cross-sectional view of the airbag of FIG. 6. 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; 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; FIG. 10 is a partially enlarged cross-sectional view showing the vicinity of an inflator arrangement position in an occupant protection device according to another embodiment of the present invention. 11 is a partially enlarged side view showing the vicinity of an inflator arrangement portion in the occupant protection device of FIG. 10. FIG.

An embodiment of the present invention will now be described with reference to the drawings. As shown in Figures 1 to 3, the occupant protection device S of this embodiment is mounted on a vehicle seat 1 and includes a seat belt 7 that forms a retaining belt portion that holds an airbag 45, an airbag 45, and an inflator 20 that supplies inflation gas to the airbag 45.

Seat 1 has a backrest 2 and a seat 3, and is supported by a seat frame 4. In this embodiment, the vehicle in which seat 1 is installed is a right-hand drive vehicle (details not shown), and seat 1 is the passenger seat. That is, seat 1 is installed in the vehicle with the right side positioned in the center of the vehicle width and the left side positioned on the outside of the vehicle width.

In this embodiment, the seat belt 7 is mounted on the seat 1 and includes a belt body 8 for protecting 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 secured to a winding shaft of a retractor (not shown) located within the backrest 2, and the other end is secured to an anchor member 14 (see Figures 1 and 2) located to the left of the rear end 3a of the seat cushion 3 of the seat 1. Specifically, the belt body 8 is positioned so that it is exposed to the outside from the upper left edge of the backrest 2. In this embodiment, when the occupant MP is not seated, the lap belt 10, which serves as a retaining belt for retaining the airbag 45, is exposed to the front of the backrest 2, as shown in Figures 1 and 2. 1, when the occupant MP is not seated, the lap belt 10 is exposed at the front of the backrest 2 at the left edge 2a of the backrest 2, extending generally along the vertical direction. The belt main body 8 includes the lap belt 10 and a shoulder belt 9 stored in the backrest 2. When the occupant MP is seated, with the tongue plate 12 connected to the buckle 13, the lap belt 10, which is positioned generally 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 positioned 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 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 the cover 70, which will be described later, form a retaining belt portion that stores and holds the folded airbag 45. In the seat belt 7, a retractor (not shown) located in the backrest 2 has a pretensioner mechanism.

As shown in Figures 4 and 5, the inflator 20, which supplies inflation gas to the airbag 45, includes an inflator body 21 and a connecting pipe 25 extending from the inflator body 21 and connecting the inflator body 21 to the airbag 45.

The inflator body 21 has a generally cylindrical outer shape and is disposed in the lower rear area of the seat cushion 3 of the seat 1, with its axial direction generally aligned with the left-right direction, as shown in Figure 4. The inflator body 21 is configured so that a gas discharge portion 22 capable of discharging inflation gas is disposed at one axial end. In this embodiment, the inflator body 21 is attached to the rear side of the seat frame 4 (rear portion 5 of the seat frame 4) located below the seat cushion 3, using a bracket 35 located on the outer periphery, with the end of the gas discharge portion 22 facing leftward. More specifically, the inflator body 21 is disposed in approximately the left half of the rear side (rear portion 5) of the seat frame 4, with the gas discharge portion 22 located at its left end 21a generally aligned with the left end of the seat frame 4 (see Figures 4 and 5). A connector 23, to which a lead wire 23a extending from an activation circuit (not shown) is connected, is connected to the other axial end (right end 21b) of the inflator body 21. A bracket 35 for attaching the inflator body 21 to the rear portion 5 of the seat frame 4 includes a retaining ring 35a having a generally annular outer shape capable of holding the inflator body 21, and a bolt 35b protruding from the retaining ring 35a. Although not shown in detail, the retaining ring 35a is configured to hold the inflator body 21 by being crimped to reduce its diameter. The brackets 35 are positioned at two locations spaced apart along the axial direction of the inflator body 21. The inflator body 21 is held by the retaining rings 35a. The inflator body 21 is attached to the seat frame 4 (rear region 5) by inserting bolts 35b protruding from the retaining rings 35a into mounting holes 5a formed in the rear region 5 of the seat frame 4 and fastening them with nuts 5b (see FIG. 5). In this embodiment, the inflator body 21 is configured to initiate activation later than the pretensioner mechanism of the seat belt 7 in order to restrict the belt body 8 of the seat belt 7 from being pulled out due to inflation of the airbag 45. In this embodiment, the inflator body 21 is configured to activate upon impact from the front and side (left) when the seat 1 is positioned facing the front of the vehicle.

The connecting pipe 25 connecting the inflator body 21 and the airbag 45 is made of a metal pipe such as steel. It extends from the inflator body 21, bends, and is positioned in a region to the side of the seat 3. In this embodiment, the connecting pipe 25 extends from the left end 21a (gas discharge port 22) of the inflator body 21, bends, and is positioned in a region to the left of the seat 3 (the outer side of the seat 3 in the vehicle width direction). The connecting pipe 25 has a generally L-shaped outer shape and is configured to include a base portion 26 on the inflator body 21 side, a tip portion 27 positioned to intersect with the base portion 26 and face the airbag 45, and a bent portion 28 between the base portion 26 and the tip portion 27. When mounted on a vehicle, the base portion 26 is positioned generally laterally along the inflator body 21, while the tip portion 27 is positioned generally perpendicular to the base portion 26 and extends forward and upward from the bent portion 28 when mounted on a vehicle. The base end 26a of the connecting pipe portion 25 is connected to the gas discharge portion 22 of the inflator body 21 by crimping (details not provided). The tip 27a of the tip portion 27 of the connecting pipe portion 25 is connected to the tip 55a of a conduit portion 55 (described later) of the airbag 45 using a clamp 38.

A connecting member 30 is disposed on the connecting pipe portion 25, connecting the base portion 26 and the tip portion 27 with the bent portion 28 sandwiched therebetween. The connecting member 30, like the connecting pipe portion 25, is made of sheet metal such as steel. In this embodiment, the connecting member 30 is disposed so as to connect the vicinity of the tip 27a of the tip portion 27 to the vicinity of the base end 26a of the base portion 26 (see Figure 4). More specifically, the connecting member 30 is disposed so as to connect the opposing surfaces (the right side surface 27b and the front side surface 26b) of the tip portion 27 and the base portion 26. The connecting member 30 restricts the tip portion 27 from moving toward the seat 3 (rightward movement) when an external force F acts on the seat 3 from the left or right side (in this embodiment, the left, outward in the vehicle width direction) (see Figure 5). It also serves as a support member for the tip portion 27.

The airbag 45 is held by the lap belt 10 of the seat belt 7, which serves as the retaining belt portion, while being folded into a long shape and surrounded by a cover 70. Specifically, when the seat belt 7 is fastened, the airbag 45 is placed in the area of the lap belt 10, covered by the cover 70, and overlaps the upper surface of the lap belt 10 (see FIG. 3). In other words, the airbag 45 is folded and stored in the gap between the lap belt 10 and the cover 70. In addition, when the airbag 45 is not fastened as shown in FIG. 1, the airbag 45 is placed on the rear side (backrest 2 side) of the lap belt 10, which is exposed at the front of the backrest 2. The cover 70 is made of a flexible sheet and is configured to break at a predetermined location when the airbag 45 is deployed and inflated, allowing the bag body 46 (described later) of the airbag 45 to protrude.

As shown in Figures 6 and 7, the airbag 45 includes a bag body 46 that inflates to protect the occupant MP, a conduit 55 that connects to the inflator 20 and allows inflation gas to flow into the bag body 46, and an attachment portion 57 that secures the bag body 46 to the lap belt 10.

The bag body 46 has an external shape upon full inflation that is a generally triangular prism with its axis generally aligned in the left-right direction. When viewed from the left or right, the fully inflated shape is a generally right-angled triangle with a hypotenuse at the front, and when viewed from the front-rear direction, the fully inflated shape is a generally rectangular shape with wider top and bottom (see Figures 8 and 9). As shown in Figures 6 and 7, the bag body 46 has a rear wall 48 positioned on the occupant MP side (rear side) upon full inflation, a front wall 47 positioned opposite the rear wall 48 in the front-rear direction, a bottom wall 49 positioned at the bottom end upon full inflation, and left and right wall portions 50 and 51 positioned opposite each other in the left-right direction upon full inflation. Upon full inflation, the bag body 46 receives the upper body MU of the occupant MP with the rear wall 48. When the upper body MU is received by the rear wall 48, the lower wall 49 abuts against and supports the thighs MT of the occupant MP, thereby protecting the occupant MP (see FIG. 9 ). The bag body 46 has a conduit 55 located on the underside of the rear end 49a of the lower wall 49, through which inflation gas from the inflator 20 (inflator body 21) flows into the bag body. In the area of the rear end 49a of the lower wall 49, two circular communication holes 53 communicating with the conduits 55 are provided side by side on the left and right sides in this embodiment. The bag body 46 is connected to the conduits 55 at the periphery of the communication holes 53.

The conduit 55 extends leftward from the bag body 46 and is generally cylindrical with an open tip 55a. The conduit 55 is connected to the connecting pipe 25. When the airbag 45 is fully inflated, the conduit 55 is positioned generally along the left-right direction so as to generally follow the lap belt 10 (see FIGS. 8 and 9). The tip 55a of the conduit 55 is connected to the tip 27a of the tip portion 27 of the connecting pipe 25 using the clamp 38, as described above. The attachment portion 57, which attaches the bag body 46 to the lap belt 10, is sewn to the underside of the conduit 55, as shown in FIGS. 6 and 7. The attachment portion 57 is generally cylindrical with open ends so that the lap belt 10 can be inserted therethrough. By inserting the lap belt 10 through the attachment portion 57, the airbag 45 is connected to the lap belt 10 and is held by the lap belt 10.

In the occupant protection device S of this embodiment, when an occupant MP is seated in a vehicle seat 1 wearing a seat belt 7, and the inflator 20 is activated, inflation gas is discharged from the inflator body 21 and flows into the bag body 46 via the connecting pipe portion 25 and the conduit portion 55. The bag body 46 of the airbag 45 then ruptures the cover 70, protruding forward and upward from the lap belt 10 serving as the retaining belt portion, and completes inflation as shown in Figures 8 and 9.

In the occupant protection device S of this embodiment, the inflator 20 has a connecting pipe portion 25 connecting the inflator main body 21 and the airbag 45, which is configured to be bent while extending from the inflator main body 21. However, the tip end portion 27 on the airbag 45 side is supported by a connecting member 30, which serves as a support member. Therefore, even if a large impact force (external force) F is applied from the left or right side (from the left in this embodiment), such as when a vehicle enters from the side, the connecting pipe portion 25 can be prevented from deforming, starting from the bent portion 28, so that the tip end portion 27 approaches the seat portion 3 (specifically, the seat frame 4). As a result, when the inflator main body 21 is activated in the event of a secondary collision following the application of an impact force from the side (from the left), the inflation gas discharged from the inflator main body 21 is smoothly delivered to the airbag 45 (bag main body 46) via the connecting pipe portion 25. This allows the inflation gas to flow into the seat 3, allowing the airbag 45 (bag body 46) to inflate smoothly. In particular, in the occupant protection device S of this embodiment, the connecting pipe portion 25 is configured to be disposed on the outer side of the seat 3 in the vehicle width direction, and therefore it is conceivable that a large impact force will act directly on the connecting pipe portion 25 due to a vehicle entering the seat 3. However, as described above, because the connecting pipe portion 25 is supported by the connecting member 30 as a support member, deformation can be suppressed even if a large impact force due to a vehicle entering the seat 3 acts directly on the connecting pipe portion 25, allowing the inflation gas to flow smoothly into the airbag 45.

Therefore, with the occupant protection device S of this embodiment, the airbag 45 can be smoothly inflated even if a secondary collision occurs after a side impact force is applied.

Specifically, in the occupant protection device S of this embodiment, the connecting member 30 connecting the base portion 26 and the tip portion 27 of the connecting pipe portion 25 constitutes a support member that supports the tip portion 27. This allows the support member to be handled integrally with the connecting pipe portion, which is preferable for ease of handling. In this embodiment, the connecting member 30 is configured to connect the opposing right side surface 27b and front side surface 26b of the tip portion 27 and the base portion 26, but the position of the connecting member is not limited to this embodiment. For example, the connecting member may be configured to connect the upper and lower surfaces of the tip portion and base portion, respectively, on the upper and lower surfaces of the connecting pipe portion, as long as it is possible to suppress deformation that would bring the tip portion closer to the seat.

10 and 11, the support member 75 may not be attached to the connecting pipe portion 25A, but may be configured to protrude from the seat frame 4A. Specifically, the support member 75 is formed to protrude leftward from near the rear end of the left side surface of the seat frame 4A (left side portion 6A of the seat frame 4A) toward the tip portion 27A of the connecting pipe portion 25A. When the inflator 20A (inflator body 21 with the connecting pipe portion 25A attached) is attached to the seat frame 4A, the support member 75 is disposed to the right of the tip portion 27A, leaving a slight gap between the tip portion 27A and the inflator 20A. The gap between the tip surface 75a of this support member 75 and the tip portion 27A is set to a dimension that allows the support member 75 and tip portion 27A to remain non-contacting when installed in the vehicle, and that allows the tip surface 75a of the support member 75 to abut against the surface of the tip portion 27A facing the support member 75 (right side surface 27b) and support the tip portion 27A when an external force F acts on the seat 3 from either the left or right side (left). The connecting pipe portion 25A has the same configuration as the connecting pipe portion 25 of the inflator 20 described above, except that it does not have a connecting member. Therefore, identical components are designated with the same reference numerals followed by the letter "A" and detailed description thereof will be omitted.

Even when the support member 75 is configured in this manner, if a large impact force (external force) F acts from the left or right side (from the left in this embodiment), such as when a vehicle approaches from the side, even if the connecting pipe portion 25A attempts to move toward the seat portion 3 (to the right), the right side surface 27b instantly comes into contact with the support member 75 and is supported by the support member 75 (see the two-dot chain line in Figure 11), preventing the tip portion 27A from deforming from the bent portion 28A toward the seat portion 3 (specifically, approaching the seat frame 4).

In the occupant protection device S of the embodiment, the lap belt 10 of the seat belt 7 is used as the retaining belt portion that holds the airbag 45. However, the retaining belt portion that holds the airbag is not limited to a lap belt. For example, a belt separate from the seat belt may be placed in front of the occupant's waist when seated in the seat, and the airbag may be held by this belt. Furthermore, in the occupant protection device S of the embodiment, although the airbag 45 is held by the lap belt 10 of the seat belt 7, the inflator 20 operates with a delay relative to the activation of the pretensioner mechanism of the seat belt 7. Therefore, the airbag 45 can be inflated while the occupant MP is stably maintained seated in the seat 1 by the seat belt 7, and the airbag 45 and the seat belt 7 provide stable protection for the occupant MP.

In addition, in the occupant protection device S of this embodiment, the seat belt 7 and inflator 20 are 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 or rotating it significantly forward and backward, the occupant MP seated in the seat 1 can be adequately protected by the airbag 45.

1...seat, 3...seat portion, 4, 4A...seat frame, 20, 20A...inflator, 21...inflator body, 25, 25A...connecting pipe portion, 26, 26A...base portion, 27, 27A...tip portion, 28, 28A...bent portion, 30...connecting member (support member), 45...airbag, 75...support member, MP...occupant, S...occupant protection device.

Claims (1)

It is configured to protect the occupant seated in the seat,
an airbag configured to be inflatable in a bag shape so as to cover the front of the occupant and to be held in a folded state by a holding belt portion that is wrapped around the waist of the occupant;
an inflator that supplies inflation gas to the airbag;
An occupant protection device having a configuration comprising:
The inflator is
an inflator body having a generally cylindrical shape and disposed in a region below the rear surface of the seat portion of the seat with its axial direction generally aligned with the left-right direction;
a connecting pipe portion that is bent while extending from the inflator body and is disposed in a region to the side of the seat portion, and that connects the inflator body and the airbag;
The device is configured to include:
the connecting pipe portion is configured to include a base side portion that is on the inflator main body side and a tip side portion that is disposed so as to intersect with the base side portion and is on the airbag side, and the tip side portion is configured to be supported by a support member so as to restrict the approach of the tip side portion to the seat side when an external force acts on the seat side from either the left or right side ,
The occupant protection device is characterized in that the support member is arranged so as to straddle the bent portion and connect the base portion side portion and the tip portion side portion .