JP7715059B2 - Side airbag device - Google Patents

Description

The present invention relates to a side airbag device mounted on a vehicle seat.

Vehicle side airbag devices that are stored on the side support side of a seatback and are configured so that gas ejected from an inflator is distributed toward the lumbar chamber and head chamber via an inner tube during a side collision of the vehicle are conventionally known (see, for example, Patent Document 1).

JP 2011-105107 A

However, in the above-mentioned side airbag devices capable of restraining the occupant's waist and head, the waist chamber deploys outside the lap belt. As a result, there is a space between the lap belt and the occupant's waist, and there is a risk that the occupant's waist will not be restrained until the side door, which applies a reaction force to the occupant's waist chamber, enters (fills the space). As such, there is still room for improvement in terms of ensuring initial restraint performance for the occupant's waist.

The present invention therefore aims to provide a side airbag device that can ensure initial restraint performance for the occupant's hips.

In order to achieve the above object, a first aspect of the present invention provides a side airbag device comprising: a side airbag body having a lumbar chamber that inflates and deploys to restrain the lumbar region of an occupant in the event of a side collision of the vehicle; and a head chamber that is formed integrally with the lumbar chamber and inflates and deploys to restrain the head of the occupant; and a tubular member that is provided inside the side airbag body and extends in the vertical direction of the seat, distributing gas ejected from an inflator to the lumbar chamber and the head chamber, wherein a protrusion is formed at the lower end of the tubular member that protrudes toward the front of the seat and above the seat and has a gas ejection port at its tip in the protruding direction, and when the gas is ejected from the ejection port of the protrusion, the lumbar chamber inflates and deploys toward the front of the seat as it passes between a lap belt that is stretched across the width of the seat and the buttocks of the occupant.

According to the first aspect of the invention, in the event of a side collision of the vehicle, the gas ejected from the inflator is distributed to the lumbar chamber and the head chamber by a tubular member provided inside the side airbag body so as to extend in the vertical direction of the seat , causing the lumbar chamber and the head chamber to inflate and deploy.

The cylindrical member has a protrusion at its lower end that protrudes toward the front and upper sides of the seat and has a gas outlet at its tip. When gas is ejected from the outlet, the lumbar chamber inflates and deploys toward the front of the seat , passing between the lap belt that spans the seat width direction and the occupant's hips. In other words, the lumbar chamber is positioned between the lap belt and the occupant's hips (including the buttocks).

Therefore, there is no space between the lap belt and the occupant's waist (including buttocks), and the occupant's waist is restrained even if a side door does not enter and apply a reaction force to the waist chamber. In other words, according to the present invention, initial restraint performance for the occupant's waist is ensured. Note that "during a vehicle side collision" in this invention includes not only when a vehicle side collision is detected, but also when a vehicle side collision is predicted.

As described above, the present invention ensures initial restraint performance for the occupant's lower back.

FIG. 2 is a side view showing the side airbag device according to the present embodiment after inflation and deployment. FIG. 2 is a front view showing the side airbag device according to the present embodiment after inflation and deployment. 2 is a schematic enlarged cross-sectional view taken along the line XX in FIG. 1. FIG. 2 is a side view showing a stored state of the side airbag device according to the embodiment. 5 is a schematic enlarged cross-sectional view taken along the line YY in FIG. 4. FIG. 6 is a schematic enlarged cross-sectional view corresponding to FIG. 5 of a side airbag device according to a modified example of the present embodiment. 10 is a graph showing the relationship between the waist restraining force and the amount of waist movement by a side airbag device, comparing the case where the side airbag body is disposed inside and the case where it is disposed outside the lap belt.

Embodiments of the present invention will now be described in detail with reference to the drawings. For ease of explanation, the arrow UP shown in each drawing indicates the upward direction of the vehicle and vehicle seat, the arrow FR indicates the forward direction of the vehicle and vehicle seat, and the arrow RH indicates the rightward direction of the vehicle and vehicle seat. Therefore, in the following description, unless otherwise specified, when up/down, front/rear, and left/right directions are mentioned, they refer to up/down, front/rear, and left/right with respect to the vehicle and vehicle seat. Furthermore, the left/right direction is synonymous with the vehicle width direction and seat width direction.

In this embodiment, the vehicle seat 10 on the left front seat of the vehicle is used as an example. Furthermore, "occupant P" in this embodiment refers, as an example, to an occupant corresponding to AM50 (50th percentile of adult American males) of the WorldSID (World Side Impact Dummy).

As shown in Figures 1 and 2, a vehicle seat 10 equipped with a side airbag device 30 according to this embodiment includes a seat cushion 12 on which an occupant P sits (supporting the buttocks Pb and thighs of the occupant P), a seatback 14 that supports the back of the occupant P, and a headrest 16 that supports the head Ph of the occupant P.

In a side view looking in the vehicle width direction (seat width direction), the seat cushion 12 extends in the front-to-rear direction, and the seat back 14 is rotatably connected to the rear end of the seat cushion 12 and extends in the up-down direction. The headrest 16 is mounted at the upper end of the seat back 14 in the center of the seat width direction and is configured to be able to move up and down. As shown in Figure 3, the seat back 14 has a cushion pad 14A and a cover 14B that covers the cushion pad 14A, and the seat cushion 12 is similar.

The vehicle seat 10 also includes a seatbelt device 20 that restrains an occupant P. As shown in FIG. 2, the seatbelt device 20 includes a webbing 22 formed in a long strip shape, a tongue plate 24 through which the webbing 22 is threaded, a buckle 26 to which the tongue plate 24 is detachably attached, a retractor (not shown), and a shoulder anchor (not shown).

One end of the webbing 22 is retracted and retracted by a retractor located inside the center pillar (not shown). The webbing 22 pulled out from the retractor is wrapped around and supported by a shoulder anchor located at the upper part of the center pillar on the passenger compartment side. The other end of the webbing 22 is fixed to a belt anchor (not shown) located on the top surface of the floor panel 18 on the left side of the seat cushion 12.

Webbing 22 is passed through the through-hole in the tongue plate 24, allowing the tongue plate 24 to move along the webbing 22. A buckle 26 is provided on the right side of the seat cushion 12. When the webbing 22 is pulled out and the tongue plate 24 is attached to the buckle 26, the occupant P is restrained in the vehicle seat 10 by the webbing 22.

In other words, with the tongue plate 24 attached to the buckle 26, the webbing 22 is stretched diagonally from the occupant P's left shoulder Ps to the right side of the occupant P's waist Pw, and also stretched in the seat width direction from the right side to the left side of the occupant P's waist Pw. In the following, the portion of the webbing 22 that stretches diagonally and restrains the occupant P's chest Pc (upper body) to the seat back 14 will be referred to as the shoulder belt 22A, and the portion of the webbing 22 that stretches in the seat width direction and restrains the occupant P's waist Pw to the seat cushion 12 will be referred to as the lap belt 22B.

The retractor is also equipped with a pretensioner mechanism that activates when a collision is detected and forcibly retracts the webbing 22. Therefore, even if the webbing 22 attempts to be suddenly pulled forward during a frontal collision, the retractor's emergency locking mechanism will activate and prevent the webbing 22 from being pulled out.

As shown in Figures 1 and 2, the side airbag device 30 includes an inflator 32 (see Figure 1) embedded in the left side portion (hereinafter referred to as the "left side") of the seatback 14, a side airbag main body 34, and a sock 40 serving as a tubular member provided inside the side airbag main body 34. The inflator 32 is a cylindrical gas generator formed in a substantially cylindrical shape, and its axial direction is aligned with the side frames 28 (see Figure 1) that form the framework of both the left and right sides of the seatback 14 (substantially the vertical direction).

The lower end 32A of the inflator 32 is connected to the connection portion 42 of the sock 40 (see Figure 1). The lower end 32A of the inflator 32 is provided with a gas ejection portion (not shown), and when a side collision of the vehicle is detected or predicted (hereinafter referred to as "side collision"), gas is ejected from the gas ejection portion and instantly supplied to the inside of the sock 40, and then supplied to the side airbag body 34 via the sock 40.

As shown in Figures 1 to 3, the side airbag body 34 has a waist chamber 36 that inflates and deploys between a portion of the lap belt 22B (hereinafter referred to as the "inner side surface") and the side of the occupant P's waist Pw (including the buttocks Pb) and between the side of the vehicle compartment (a side door, not shown) and the side of the occupant P's chest Pc, and a head chamber 38 that inflates and deploys between a portion of the shoulder belt 22A above the occupant P's shoulder Ps (hereinafter referred to as the "upper rear surface") and the side of the occupant P's head Ph.

As shown in FIG. 1, the lumbar chamber 36 extends from the upper end to the lower end of the seat back 14 (all the way to the seat cushion 12) in a side view, and is formed into a generally elliptical shape with its approximate vertical center bulging forward. Meanwhile, the head chamber 38 is formed into a generally rectangular shape with its longitudinal direction extending in the front-to-rear direction in a side view, and is formed large enough to cover the entire side of the occupant P's head Ph.

The side airbag body 34 is formed into a single bag by sewing the outer edges of two pieces of base fabric together, and the lumbar chamber 36 and head chamber 38 are formed as a single unit. A sock 40 extending generally in the vertical direction is provided inside the side airbag body 34 by being sewn together with the side airbag body 34.

As shown in Figures 1 and 2, the sock 40 distributes the gas ejected from the inflator 32 to the lumbar chamber 36 and the head chamber 38, and has an outlet 43 formed at its upper end for ejecting the gas. As shown in Figures 1 to 3, the lower end of the sock 40 has an extension 44 formed therein that faces the side of the occupant P's buttocks Pb and the inner side of the side of the lap belt 22B across the lumbar chamber 36 in the vehicle width direction (seat width direction) after the lumbar chamber 36 is inflated and deployed.

In other words, the lower end of the lumbar chamber 36, including the extension 44, is positioned between the inner side surface of the lap belt 22B and the side of the occupant P's buttocks Pb, filling the space between them. The extension 44 is also integrally formed with a protrusion 46 that inflates and deploys together with the lumbar chamber 36 when gas is supplied into the sock 40, and protrudes forward beyond the lap belt 22B. In other words, the sock 40 is formed in a roughly "L" shape in a side view from the right side of the vehicle (see Figure 1). The protruding tip of the protrusion 46 is formed with an outlet 48 for ejecting gas.

As shown in FIG. 1, the connection portion 42 is provided so as to protrude rearward and upward from the rear surface of the sock 40. That is, the connection portion 42 provided on the rear surface of the sock 40 has an insertion hole (not shown) into which the lower end portion 32A of the inflator 32 can be inserted. The lower end portion 32A of the inflator 32 is inserted into the insertion hole, and the connection portion 42 is configured to prevent gas from leaking between the insertion hole and the outer peripheral surface of the inflator 32.

As shown in Figures 4 and 5, the side airbag body 34 is stored in a folded state in a storage space Sr (see Figure 5) formed inside the seatback 14, from the lower end to the upper end of the left side. An upper frame (not shown) that integrally connects the upper ends of the left and right side frames 28 is provided at the upper end inside the seatback 14, and the side airbag body 34 is stored along the left side frame 28 and the left end of the upper frame.

More specifically, the waist chamber 36 is stored along the left side frame 28, and the lower front end 36A of the waist chamber 36, including the protruding portion 46 of the sock 40, is folded in an accordion-like manner as shown in FIG. 5. In other words, when stored, the lower end (including the lower front end 36A) of the waist chamber 36 has its accordion-like folded portion protruding forward, as shown in FIG. 4. The lower front end 36A of the waist chamber 36 may also be rolled outward, as shown in FIG. 6, in which case the lower end (including the lower front end 36A) of the waist chamber 36 has its rolled portion protruding forward.

In addition, although not shown, the head chamber 38 is folded, for example, from top to bottom and bottom to top in a roughly "Z" shape when viewed from the front, then rolled up with the vertical axis as the axial direction and stored along the left end of the upper frame. Therefore, when inflated and deployed, the head chamber 38 is configured so that first the rolled-up portion unwinds and deploys forward, and then deploys in the vertical direction.

In addition, a portion of the skin 14B extending from the lower end to the upper end on at least the left side of the seat back 14 (hereinafter referred to as "skin 14C"; see Figures 3, 5, and 6) is configured to be rupturable by the inflating and deploying side airbag body 34. In other words, the side airbag body 34 stored in the storage space Sr within the seat back 14 is inflated and deployed by gas supplied from the inflator 32 in the event of a side collision from the left side of the vehicle, and the skin 14C extending from the lower end to the upper end on the left side of the seat back 14 is configured to be easily ruptured by the inflation pressure of that gas.

A portion of the cushion pad 14A is located inside the surface skin 14C, but this portion of the cushion pad 14A is thinner than the other portions and can therefore be broken by the inflating side airbag body 34. The side airbag body 34, which inflates and deploys by breaking through part of the cushion pad 14A and the surface skin 14C of the seatback 14, is positioned outside the occupant P in the seat width direction.

Specifically, the waist chamber 36 inflates toward the space between the inner side of the lap belt 22B and the side of the occupant P's waist Pw (including buttocks Pb) and between the side of the vehicle compartment (side door) and the side of the occupant P's chest Pc. The waist chamber 36 is positioned between the inner side of the lap belt 22B and the side of the occupant P's waist Pw (including buttocks Pb) and between the side of the vehicle compartment (side door) and the side of the occupant P's chest Pc, covering the side of the occupant P from the shoulders Ps to the waist Pw (including buttocks Pb) (see Figures 1 and 2).

The head chamber 38, which inflates toward the space between the upper rear surface of the shoulder belt 22A and the left side of the headrest 16, is positioned between the upper rear surface of the shoulder belt 22A and the side of the occupant P's head Ph, covering the side of the occupant P's head Ph (see Figures 1 and 2). A vent hole (not shown) is formed at the front end of the lumbar chamber 36 to prevent the internal pressure of the side airbag main body 34 from becoming excessive. The vent hole is formed, for example, by leaving a portion of the base fabric of the side airbag main body 34 unsewn.

The operation of the side airbag device 30 according to this embodiment, which is configured as described above, will now be explained.

During a side collision from the left side of the vehicle, gas is instantly supplied from the inflator 32 to the inside of the sock 40, and then distributed through the sock 40 to the lumbar chamber 36 and head chamber 38 of the side airbag body 34. The internal pressure (inflation pressure) of the side airbag body 34, which begins to inflate due to the gas supply, causes the upholstery 14C from the bottom to the top on the left side of the seat back 14 to rupture, along with part of the cushion pad 14A.

In other words, when gas is supplied to the inside of the sock 40, the extension 44 at its lower end expands, and gas is ejected from the outlet 48 formed at the tip of the protruding portion 46 in the protruding direction, causing the accordion-shaped (or rolled) lower front end 36A of the lumbar chamber 36 to unfold and protrude forward. Then, because the lower front end 36A of the lumbar chamber 36, including the protruding portion 46, was positioned to the left rear of the occupant P's buttocks Pb, it inflates and deploys toward the space between the inner side of the side of the lap belt 22B and the left side of the occupant P's buttocks Pb.

In other words, as the protrusion 46 inflates and deploys from the left rear side of the occupant P's buttocks Pb toward the front side together with the lower front end 36A of the lumbar chamber 36, the lower front end 36A of the lumbar chamber 36, including the protrusion 46, passes inside the lap belt 22B (see FIG. 3). As a result, the lower end of the lumbar chamber 36, including the protrusion 46 and extension 44, is positioned between the inner side of the side of the lap belt 22B and the left side of the occupant P's lumbar region Pw, including the occupant P's buttocks Pb, filling the space between them (see FIGS. 1 and 2).

Furthermore, as gas is ejected from the ejection port 48, the upper portion of the lumbar chamber 36 above the lower end (the portion over which the lap belt 22B is entrained) inflates and deploys toward the space between the side of the vehicle compartment (the side door) and the left side of the occupant P's chest Pc. As a result, the upper portion of the lumbar chamber 36 above the lower end (the portion over which the lap belt 22B is entrained) is positioned between the side of the vehicle compartment (the side door) and the left side of the occupant P's chest Pc (see Figures 1 and 2).

As a result, the left side of the occupant P, from the shoulders Ps through the waist Pw to the buttocks Pb, is covered from the left side by the waist chamber 36. Therefore, in the event of a side collision from the left side of the vehicle, the chest Pc and waist Pw (including the buttocks Pb) of the occupant P can be restrained by the waist chamber 36.

Furthermore, in this embodiment, the lower end of the lumbar chamber 36 is positioned (sandwiched) between the inner side surface of the lap belt 22B and the side surface of the occupant P's buttocks Pb. Therefore, compared to when the lower end of the lumbar chamber 36 is positioned outside the lap belt 22B, no space is formed (exists) between the inner side surface of the lap belt 22B and the lumbar region Pw (including the buttocks Pb) of the occupant P. Therefore, even if a side door that applies a reaction force to the lumbar chamber 36 does not enter the vehicle widthwise inward, the reaction force can be absorbed by the lap belt 22B, and the lower end of the lumbar chamber 36 can effectively restrain the lumbar region Pw (including the buttocks Pb) of the occupant P.

In other words, this embodiment ensures initial restraint performance for the lumbar region Pw (including buttocks Pb) of the occupant P. Figure 7 shows the load-displacement characteristics (FS characteristics). As shown in Figure 7, when the lower end of the lumbar chamber 36 is positioned outside the lap belt 22B, the profile is as shown by the dashed line. However, when the lower end of the lumbar chamber 36 is positioned inside the lap belt 22B, the profile is as shown by the solid line, and it can be seen that initial restraint performance for the lumbar region Pw (including buttocks Pb) of the occupant P is improved.

In addition, because the lower end of the lumbar chamber 36 is positioned between the inner side surface of the lap belt 22B and the side of the occupant P's buttocks Pb, the tension of the lap belt 22B can be used to improve the initial restraining force on the occupant P's lumbar region Pw (including the buttocks Pb). Furthermore, the high-pressure extension 44, which faces the occupant P's buttocks Pb in the vehicle width direction, can restrain the center of gravity of the occupant P's lumbar region Pw seated in the vehicle seat 10 with a high load via the inflated lumbar chamber 36. Therefore, the occupant P's lumbar region Pw (including the buttocks Pb) can be efficiently restrained in the event of a side collision of the vehicle.

On the other hand, when gas is supplied to the inside of the sock 40, the gas is ejected from the outlet 43 formed at the upper end thereof, and the head chamber 38, which is folded as described above, unfolds and inflates into the space between the upper rear surface of the shoulder belt 22A and the left side of the headrest 16.

As a result, the head chamber 38 is positioned between the upper rear surface of the shoulder belt 22A and the left side of the occupant P's head Ph, and the left side of the occupant P's head Ph is covered from the left side by the head chamber 38. Therefore, in the event of a side collision from the left side of the vehicle, the occupant P's head Ph can be restrained by the head chamber 38.

The side airbag device 30 according to this embodiment has been described above with reference to the drawings, but the side airbag device 30 according to this embodiment is not limited to the one shown in the drawings, and design changes can be made as appropriate within the scope of the gist of the present invention. For example, the size of the outlet 43 and the size of the outlet 48 may be the same, but it is preferable that the size of the outlet 48 is larger than the size of the outlet 43, as this allows the waist chamber 36 of the side airbag body 34 to be deployed more quickly.

22B Lap belt 30 Side airbag device 32 Inflator 34 Side airbag body 36 Waist chamber 38 Head chamber 40 Sock (cylindrical member)
46 Projection 48 Spout P Passenger Pb Buttocks Ph Head Pw Waist

Claims (2)

a side airbag body having a lumbar chamber that inflates and deploys to restrain the lumbar region of an occupant in the event of a side collision of the vehicle, and a head chamber that is formed integrally with the lumbar chamber and inflates and deploys to restrain the head of the occupant;
a tubular member provided inside the side airbag body so as to extend in the seat vertical direction, and which distributes gas ejected from the inflator to the lumbar chamber and the head chamber;
Equipped with
A protrusion is formed at the lower end of the tubular member, which protrudes toward the front and upper sides of the seat and has a gas outlet at its tip in the protruding direction, and when the gas is ejected from the outlet of the protrusion, the lumbar chamber inflates and deploys toward the front side of the seat by passing between a lap belt that is stretched across the width of the seat and the buttocks of the occupant. 2. The side airbag device according to claim 1, wherein, when the lumbar chamber is fully inflated and deployed, the outlet of the protrusion is located, in a plan view, on a seat front side of a portion of the lap belt that is stretched across the lumbar chamber.