JP7605083B2 - Vehicle seat equipped with a side airbag device - Google Patents

Description

The present invention relates to a vehicle seat equipped with a side airbag device.

In the vehicle seat safety device disclosed in the following Patent Document 1, the backrest of the vehicle seat has at least one lateral region and an upper region from which the headrest extends. The backrest is equipped with a side airbag device having at least one inflator and a side airbag. The side airbag has a chest section and a head section, and a gas generator (inflator) is housed in the chest section. When the inflator is activated, the chest section inflates and deploys from the side region of the backrest, and the head section inflates and deploys from the upper region of the backrest next to the headrest. The head section and the chest section are formed of separate bags and are connected via a tubular filling section or the like. As a result, the head section is configured to inflate and deploy shifted inward in the vehicle width direction (i.e., toward the occupant's head) relative to the chest section.

U.S. Pat. No. 8,469,395

In the above prior art, the head section inflates and deploys between the shoulder belt of the seat belt and the occupant's head, allowing the head to be restrained early by the head section. However, due to the structure in which the inflator is housed in the torso chamber, the head chamber inflates with a delay after the torso chamber inflates. Since the initial inflation pressure (internal pressure) of the head chamber is lower than the initial inflation pressure of the torso chamber, there is a delay in the tearing of the seat back skin in the inflation area of the head chamber. As a result, it is thought that there is a possibility that the inflation and deployment of the head chamber will be delayed.

In consideration of the above, the present invention aims to provide a vehicle seat equipped with a side airbag device that can suppress delays in the inflation and deployment of the head chamber between the shoulder belt and the occupant's head.

A vehicle seat equipped with a side airbag device of the first aspect includes a seat body in which an occupant is restrained using a three-point seat belt, an inflator that generates gas when a side collision of the vehicle is detected or predicted, a side airbag that is stored in a folded state along the upper end of the seat back of the seat body from the side on the outer side of the vehicle width direction through the shoulder, a torso chamber supplied with gas from the inflator inflates and deploys from the side between the occupant's torso and the vehicle body side, and a head chamber supplied with gas via the torso chamber inflates and deploys from the upper end between the occupant's head and the shoulder belt of the seat belt, a lower force cloth that connects the seat back skin and the side frame at the side and transmits the inflation pressure of the torso chamber to the skin to split the skin, and an upper force cloth that connects the seat back skin and the upper frame at the upper end and transmits the inflation pressure of the head chamber to the skin to split the skin.

In the first aspect, the occupant is restrained to the seat body using a three-point seat belt. When a side collision of the vehicle is detected or predicted, gas is generated from the inflator and supplied to the side airbag. The side airbag is stored in a folded state along the upper end of the seat back of the seat body, from the outer side in the vehicle width direction through the shoulder. The torso chamber of the side airbag is supplied with gas from the inflator, and inflates and deploys from the side of the seat back between the occupant's torso and the side of the vehicle body. The head chamber of the side airbag is supplied with gas via the torso chamber, and inflates and deploys from the upper end of the seat back between the occupant's head and the shoulder belt of the seat belt.

In this embodiment, the seat back skin and the side frame are connected by a lower force cloth at the side of the seat back, and the seat back skin and the upper frame are connected by an upper force cloth at the upper end of the seat back. The lower force cloth transmits the inflation pressure of the torso chamber to the seat back skin, causing it to split. The upper force cloth transmits the inflation pressure of the head chamber to the seat back skin, causing it to split. The addition of this upper force cloth makes it possible to suppress delays in the inflation and deployment of the head chamber between the shoulder belt and the occupant's head.

In the vehicle seat equipped with the side airbag device of the second aspect, in the first aspect, one end of the upper webbing is sewn to a tear seam provided on the skin, and the other end is fixed to the upper frame.

In the second embodiment, one end of the upper webbing is sewn to a tear seam provided on the seat back skin, and the other end of the upper webbing is fixed to the upper frame of the seat back. This allows the inflation pressure of the head chamber to be concentrated on the tear seam with a simple structure, allowing the tear seam to rupture early.

In the vehicle seat equipped with the side airbag device of the third aspect, in the second aspect, the upper webbing is looped so as to surround the head chamber stored in the upper end of the seat back.

In the third aspect, the head chamber stored in the upper end of the seat back is surrounded by a loop-shaped upper webbing. This helps stabilize the deployment behavior of the head chamber, as the expansion and deployment of the head chamber is guided by the loop-shaped upper webbing.

The vehicle seat equipped with the side airbag device of the fourth aspect is any one of the first to third aspects, in which the upper webbing is configured to be less stretchable than the lower webbing.

In the fourth aspect, the upper force cloth is configured to be less stretchable than the lower force cloth, so that the inflation pressure of the head chamber can be effectively transmitted to the seat back skin via the upper force cloth, and the seat back skin can be ripped open earlier. As a result, the head chamber can be inflated and deployed earlier.

As described above, a vehicle seat equipped with the side airbag device of the present invention can prevent delays in the inflation and deployment of the head chamber between the shoulder belt and the occupant's head.

FIG. 2 is a front view showing a state in which the side airbag in the vehicle seat according to the embodiment has been fully inflated and deployed. FIG. 2 is a side view showing a state in which the side airbag in the vehicle seat according to the embodiment has been fully inflated and deployed. FIG. 2 is a planar development view of the side airbag. 4 is an enlarged cross-sectional view showing a cut surface taken along line F4-F4 in FIG. 3; FIG. FIG. 2 is a front view showing the vehicle seat according to the embodiment, showing a see-through state of the inside of the seat back. 1 is a front view showing a vehicle seat according to an embodiment; 6 is an enlarged cross-sectional view showing a cut surface taken along line F7-F7 in FIG. 5. FIG. 8 is an enlarged cross-sectional view corresponding to FIG. 7 and illustrating a state in the middle of inflating and deploying the side airbag.

First Embodiment
A vehicle seat 10 (hereinafter, simply referred to as "vehicle seat 10") equipped with a side airbag device according to an embodiment of the present invention will be described below with reference to Figs. 1 to 8. Note that the arrow FR shown as appropriate in each drawing indicates the front of the vehicle, the arrow UP indicates the upper side of the vehicle, and the arrow LH (OUT) indicates the left side of the vehicle (outside in the vehicle width direction). Hereinafter, when the directions of front-rear, left-right, and up-down are used in the description, they will indicate front-rear in the front-rear direction of the vehicle, left-right in the left-right direction of the vehicle (vehicle width direction), and up-down in the up-down direction of the vehicle, unless otherwise specified. Also, in each drawing, some symbols may be omitted in order to make the drawings easier to read.

As shown in Figures 1 and 2, the vehicle seat 10 according to this embodiment includes a seat body 12 in which an occupant is restrained using a three-point seat belt (webbing) 32, and a side airbag device 40. As an example, this vehicle seat 10 is the driver's seat in a right-hand drive vehicle or the passenger seat in a left-hand drive vehicle, and is disposed on the right side of the vehicle interior. The front-rear direction, left-right direction (width direction), and up-down direction of this vehicle seat 10 coincide with the front-rear direction, left-right direction (width direction), and up-down direction of the vehicle. When this vehicle seat 10 is disposed on the left side of the vehicle interior, it has a left-right symmetrical configuration to this embodiment.

The seat body 12 has a seat cushion 14 that supports the buttocks and thighs of an occupant P seated on the seat body 12, a seat back 16 that is connected to the rear end of the seat cushion 14 and supports the back of the occupant P, and a headrest 18 that is connected to the upper end of the seat back 16 and supports the head H of the occupant P.

In FIG. 1 and FIG. 2, a crash test dummy P is seated in the seat body 12 in place of an actual occupant. This dummy P is, for example, an AM50 (50th percentile American adult male) of the World Side Impact Dummy (WorldSID). This dummy P is seated in the seat body 12 in a seating manner prescribed by the side impact test method. The front-to-rear position of this seat body 12 relative to the vehicle and the inclination angle of the seat back 16 relative to the seat cushion 14 are adjusted to standard setting positions corresponding to the above-mentioned seating manner. In this state, the front-to-rear, left-to-right, up-to-down directions of the seat back 16 are consistent with the front-to-rear, left-to-right, up-to-down directions of the vehicle.

The seat back 16 includes a seat back frame 20 (see Figs. 5, 7, and 8) which is a skeletal member, a seat back pad 22 (see Figs. 7 and 8) which is placed on the seat back frame 20, and a seat back skin 24 (see Figs. 1, 2, 5 to 8) which covers the seat back pad 22. The seat back frame 20 is made of, for example, metal or resin, and has a pair of left and right side frames 20A as shown in Fig. 5, and an upper frame 20B which connects the upper ends of the left and right side frames 20A in the left-right direction of the seat back 16. The seat back pad 22 is made of, for example, a foam such as urethane foam. The seat back skin 24 is made of multiple skin pieces which are made of, for example, a cloth material (woven fabric), a knit material (knitted fabric), synthetic leather, leather, etc., sewn together. The seat back skin 24 corresponds to the "skin" in this invention.

The seat belt 32 that restrains the occupant P to the seat body 12 constitutes the main part of the vehicle seat belt device 30. As shown in FIG. 1, one longitudinal end of the seat belt 32 is fixed to an anchor plate 34 that is fixed to the vehicle floor or the like on the outer side (here, the right side) of the seat body 12 in the vehicle width direction. The other end (not shown) of the seat belt 32 is fixed to a winding shaft of a retractor (not shown) disposed on the lower part of the B-pillar of the vehicle or the like. The middle part (not shown) of the seat belt 32 is inserted into a shoulder anchor (not shown) disposed on the upper part of the B-pillar or the like and folded back.

A tongue plate 36 is slidably attached to the seat belt 32 between the shoulder anchor and the anchor plate 34. This tongue plate 36 is connected to a buckle device 38 attached to the lower end of the seat body 12 on the inner side (here, the left side) of the seat body 12 in the vehicle width direction. This places the occupant P in a state in which the seat belt 32 is fastened. In this seat belt fastening state, the chest and abdomen of the occupant P are restrained by the shoulder belt 32A, which is the portion of the seat belt 32 between the shoulder anchor and the tongue plate 36. In addition, in this seat belt fastening state, the waist of the occupant P is restrained by the lap belt 32B, which is the portion of the seat belt 32 between the tongue plate 36 and the anchor plate 34.

An inflator 44 (see FIG. 2), which is a component of the side airbag device 40, is disposed on the side portion 16R on the outer side in the vehicle width direction of the seat back 16. A side airbag 42, which is a component of the side airbag device 40, is disposed on the portion extending from the side portion 16R on the outer side in the vehicle width direction of the seat back 16 through the shoulder 16S to the upper end portion 16U. As shown in FIG. 3 and FIG. 4, the side airbag 42 is formed into a bag shape by overlapping two base fabrics BC1 and BC2 formed by cutting out a nylon or polyester fabric material, for example, and sewing the outer peripheral edge portions at a sewing portion S1. The manufacturing method of the side airbag 42 is not limited to the above and can be appropriately changed. For example, the side airbag 42 may be manufactured by folding one base fabric in half and sewing the outer peripheral edge portions. For example, the side airbag 42 may be manufactured by a bag weaving method (so-called OPW method) using an automatic loom.

The side airbag 42 is configured as a single bag body and has a long bag shape. One longitudinal end of the side airbag 42 is a head chamber 42A that restrains the head H of the occupant P, and the other longitudinal end of the side airbag 42 is a torso chamber 42B that restrains the torso B of the occupant P (here, from the chest to the waist). A duct-shaped constricted portion (duct portion) 42C is formed between the head chamber 42A and the torso chamber 42B. The side airbag 42 is constricted at the constricted portion 42C.

An inflator connection portion 42D extends from one long edge of the side airbag 42. An inflator 44 is connected to the inflator connection portion 42D. The inflator 44 is a so-called cylinder-type inflator and is formed in a cylindrical shape. As shown in FIG. 2, the inflator 44 is disposed in the outer side of the seat back 16 in the vehicle width direction with its axis aligned along the height direction of the seat back 16, i.e., tilted downward toward the front, and is fixed to the side frame 20A of the seat back frame 20 on the outer side in the vehicle width direction.

A gas ejection portion is provided at the lower end of the inflator 44, and the inflator connection portion 42D of the side airbag 42 is connected to this ejection portion. As shown in FIG. 2, the inflator 44 is electrically connected to a side impact ECU 46 mounted on the vehicle. A side impact sensor 48 that detects a side impact is electrically connected to the side impact ECU 46. The side impact ECU 46 is configured to activate the inflator 44 when it detects a side impact (or the inevitability of a side impact) based on a signal from the side impact sensor 48.

When the inflator 44 is activated, gas is ejected from the ejection portion of the inflator 44 into the torso chamber 42B. The gas supplied to the torso chamber 42B is also supplied to the head chamber 42A through the narrowed portion 42C, causing the side airbag 42 to inflate and deploy. If a collision prediction sensor (pre-crash sensor) that predicts (predicts) a side collision is electrically connected to the side collision ECU 46, the inflator 44 may be configured to be activated when the side collision ECU 46 predicts a side collision based on a signal from the collision prediction sensor.

As shown in FIG. 5, the side airbag 42 is normally stored in a folded state along the upper end 16U of the seatback 16 from the side 16R on the outer side in the vehicle width direction through the shoulder 16S. In this folded state, the side airbag 42 has the torso chamber 42B located at the side 16R of the seatback 16, the constricted portion 42C located at the shoulder 16S of the seatback 16, and the head chamber 42A located at the upper end 16U of the seatback 16. This head chamber 42A is stored at the upper end 16U of the seatback 16, extending to the vicinity of the headrest support 19 on the outer side in the vehicle width direction. In addition, the constricted portion 42C is stored in a bent state along the shoulder 16S of the seatback 16.

As shown in FIG. 6, a tear seam TS is set in the seat back skin 24 from the side portion 16R on the outer side of the seat back 16 in the vehicle width direction, through the shoulder 16S, and along the upper end portion 16U of the seat back 16. This tear seam TS is composed of a lower tear seam TS1 and an upper tear seam TS2. The lower tear seam TS1 extends in the height direction of the seat back 16 at the side portion 16R of the seat back 16. The upper tear seam TS extends in the approximately left-right direction of the seat back 16 at the upper end portion 16U of the seat back 16. The boundary between the lower tear seam TS1 and the upper tear seam TS2 is set at the shoulder 16S of the seat back 16.

As shown in FIG. 7, in the upper tear seam TS2, two skin pieces 24A, 24B that form part of the seatback skin 24 are sewn together. Skin piece 24A forms the upper surface of the upper end portion 16U of the seatback 16, and skin piece 24B forms the upper part of the front surface of the side portion 16R of the seatback 16. Although not shown in cross section, in the lower tear seam TS1, multiple skin pieces that form part of the seatback skin 24 are sewn together.

The lower tear seam TS1 tears open when it receives the expansion pressure of the torso chamber 42B, and the upper tear seam TS2 tears open when it receives the expansion pressure of the head chamber 42A. The thread used to sew the upper tear seam TS2 is weaker than the thread used to sew the lower tear seam TS1 (e.g., a thread with a larger count or a thread made of a weaker material). This makes the upper tear seam TS2 easier to tear open than the lower tear seam TS1. Note that the above configuration is not limited to a configuration in which the strength (thickness, etc.) of the thread is different between the upper tear seam TS2 and the lower tear seam TS1, and the sewing pitch (pitch of the stitching) may be different between the upper tear seam TS2 and the lower tear seam TS1. If the sewing pitch of the upper tear seam TS2 is set larger than the sewing pitch of the lower tear seam TS1, the upper tear seam TS2 can be made easier to tear open than the lower tear seam TS1.

As shown in FIG. 5, two lower webbing 50, 52 are arranged side by side in the height direction of the seat back 16 on the side portion 16R of the seat back 16. An upper webbing 54 is arranged on the upper end portion 16L of the seat back 16. The lower webbing 50, 52 and the upper webbing 54 are made of a fabric material that is less stretchable than the material of the seat back skin 24.

The lower force cloths 50, 52 connect the side frame 20A on the outer side of the seatback frame 20 in the vehicle width direction to the lower tear seam TS1. These lower force cloths 50, 52 are loop-shaped when viewed from the height direction of the seatback 16 so as to surround the torso chamber 42B stored in the side portion 16R of the seatback 16. These lower force cloths 50, 52 transmit the expansion pressure of the torso chamber 42B to the lower tear seam TS1 of the seatback skin 24, tearing the lower tear seam TS1. These lower force cloths 50, 52 are conventionally known, so detailed description will be omitted.

As shown in FIG. 7, the upper webbing 54 connects the upper frame 20B of the seatback frame 20 to the upper tear seam TS2. When viewed from the left and right direction of the seatback 16, the upper webbing 54 is loop-shaped so as to surround the head chamber 42A stored in the upper end 16U of the seatback 16. Specifically, the upper webbing 54 is composed of a front upper webbing 54A located on the front side of the seatback 16 relative to the head chamber 42A in the stored state, and a rear upper webbing 54B located on the upper and rear sides of the seatback 16 relative to the head chamber 42A in the stored state. One end of each of the front upper webbing 54A and the rear upper webbing 54B is sewn together to the upper tear seam TS2.

The front upper webbing 54A is inserted through a slit 56 formed in the seat back pad 22 on the front side of the head chamber 42A, and the other end is overlapped on the front surface of the upper frame 20B. The rear upper webbing 54B is inserted through a slit 58 formed in the seat back pad 22 on the rear side of the head chamber 42A, and the other end is overlapped on the rear surface of the upper frame 20B. The other ends of the front upper webbing 54A and the rear upper webbing 54B are fastened and fixed to the upper frame 20B using bolts 60 and 62, for example. The method of fixing the other ends of the front upper webbing 54A and the rear upper webbing 54B to the upper frame 20B is not limited to the above and can be changed as appropriate. For example, a plate-shaped member may be attached to the other ends of the front upper webbing 54A and the rear upper webbing 54B, and these plate-shaped members may be fixed to the upper frame 20B using bolts or the like.

As shown in FIG. 8, the upper force cloth 54 transmits the expansion pressure of the head chamber 42A to the upper tear seam TS2 of the seat back skin 24, tearing the upper tear seam TS2. In this embodiment, the fabric material constituting the upper force cloth 54 (i.e., the front upper force cloth 54A and the rear upper force cloth 54B) is configured to be less stretchable than the fabric material constituting the lower force cloths 50, 52.

In the vehicle seat 10 configured as described above, when the inflator 44 is activated and the side airbag 42 begins to inflate, the lower tear seam TS1 and upper tear seam TS2 of the seatback skin 24 are subjected to the inflation pressure of the torso chamber 42B and the head chamber 42A and tear open. This causes the side airbag 42 to inflate and deploy between the occupant P and the side of the vehicle body (not shown). In this case, gas from the inflator 44 is supplied to the torso chamber 42B through the inflator connection portion 42D, and gas from the inflator 44 is supplied to the head chamber 42A through the torso chamber 42B and the constricted portion 42C. For this reason, the head chamber 42A inflates and deploys later than the torso chamber 42B. The inflation pressure of the head chamber 42A is lower than the inflation pressure of the torso chamber 42B. Additionally, the tear seams TS tear in the following order: below the lower tear seam TS1 → above the lower tear seam TS1 → above the upper tear seam TS2.

1 and 2, the torso chamber 42B inflates and deploys from the side 16R of the seat back 16 between the torso B of the occupant P and the side of the vehicle body (not shown). This torso chamber 42B faces the chest, abdomen, and waist of the occupant P in contact with or in close proximity from the outside in the vehicle width direction. The head chamber 42A inflates and deploys from the upper end 16U of the seat back 16 between the head H of the occupant P and the shoulder belt 32A of the seat belt 32. This head chamber 42A is disposed adjacent to the headrest 18 on the outside and front side of the vehicle width direction, and faces the head H of the occupant P in contact with or in close proximity from the outside in the vehicle width direction. Although not shown, a duct (inner tube) that distributes gas from the inflator 44 into the torso chamber 42B and the head chamber 42A may be arranged inside the side airbag 42.

<Action and Effects>
Next, the operation and effects of this embodiment will be described.

In the vehicle seat 10 configured as described above, the occupant P is restrained to the seat body 12 using a three-point seat belt 32. When a side collision of the vehicle is detected or predicted, gas is generated from the inflator 44 and supplied to the side airbag 42. The side airbag 42 is stored in a folded state along the upper end 16U of the seat back 16 of the seat body 12 from the side portion 16R on the outer side in the vehicle width direction through the shoulder 16S. The torso chamber 42B of the side airbag 42 is supplied with gas from the inflator 44 and inflates and deploys from the side portion 16R of the seat back 16 between the torso B of the occupant P and the side of the vehicle body. The head chamber 42A of the side airbag 42 is supplied with gas via the torso chamber 42B and inflates and deploys from the upper end 16U of the seat back 16 between the head H of the occupant P and the shoulder belt 32A of the seat belt 32. This side airbag 42 is made up of a single bag, so the structure can be simplified compared to when the head chamber 42A and the torso chamber 42B are made up of separate bags.

Moreover, in this embodiment, the seat back skin 24 and the side frame 20A are connected by the lower force cloths 50, 52 at the side portion 16R of the seat back 16, and the seat back skin 24 and the upper frame 20B are connected by the upper force cloth 54 at the upper end portion 16U of the seat back 16. The lower force cloths 50, 52 transmit the inflation pressure of the torso chamber 42B to the lower tear seam TS1 of the seat back skin 24, causing the lower tear seam TS1 to tear. The upper force cloth 54 transmits the inflation pressure of the head chamber 42A to the upper tear seam TS2 of the seat back skin 24, causing the upper tear seam TS2 to tear. The addition of this upper force cloth 54 can suppress delays in the inflation and deployment of the head chamber 42A between the shoulder belt 32A and the head H of the occupant P. As a result, the deployment behavior of the head chamber 42A between the shoulder belt 32A and the head H of the occupant P can be stabilized. Furthermore, the expansion and deployment of the head chamber 42A between the shoulder belt 32A and the head H of the occupant P is guided by the upper webbing 54. This makes it possible to further stabilize the deployment behavior of the head chamber 42A between the shoulder belt 32A and the head H of the occupant P.

In addition, in this embodiment, one end of each of the front upper force cloth 54A and the rear upper force cloth 54B constituting the upper force cloth 54 is sewn together with the upper tear seam TS2, and the other end of each of the front upper force cloth 54A and the rear upper force cloth 54B is fixed to the upper frame 20B. This allows the expansion pressure of the head chamber 42A to be concentrated on the upper tear seam TS2 with a simple configuration, allowing the upper tear seam TS2 to tear early.

In addition, in this embodiment, the head chamber 42A stored in the upper end portion 16U of the seat back 16 is surrounded by an upper force cloth 54 that is loop-shaped when viewed from the left and right direction of the seat back 16. This allows the inflation and deployment of the head chamber 42A to be guided by the loop-shaped upper force cloth 54, making it possible to further stabilize the deployment behavior of the head chamber 42A between the shoulder belt 32A and the head H of the occupant P.

In addition, in this embodiment, the upper force cloth 54 is configured to be less stretchable than the lower force cloths 50, 52. This allows the inflation pressure of the head chamber 42A to be effectively transmitted to the upper tear seam TS2 of the seat back skin 24 via the upper force cloth 54, and the upper tear seam TS2 can be ripped open earlier. As a result, the head chamber 42A can be inflated and deployed earlier.

Furthermore, in this embodiment, the upper tear seam TS2 is configured to be more easily torn than the lower tear seam TS1. This allows the upper tear seam TS2 to be torn early by the inflation pressure of the head chamber 42A, even in a configuration in which the inflation pressure of the head chamber 42A is lower than the inflation pressure of the torso chamber 42B. As a result, delays in the inflation and deployment of the head chamber 42A between the shoulder belt 32A and the head H of the occupant P can be more effectively prevented.

In addition, in this embodiment, the upper tear seam TS2 is sewn with a weaker thread than the lower tear seam TS1. This allows the upper tear seam TS2 to be made easier to tear than the lower tear seam TS1 with a simple configuration. This effect can be obtained even when the sewing pitch of the upper tear seam TS2 is set larger than the sewing pitch of the lower tear seam TS1.

In the above embodiment, the upper tear seam TS2 is configured to be easier to tear than the lower tear seam TS1, but this is not limited thereto, and the upper tear seam TS2 and the lower tear seam TS1 may be configured to be equally easy to tear.

In addition, in the above embodiment, the upper force cloth 54 is configured to be less stretchable than the lower force cloths 50, 52, but this is not limited thereto, and the upper force cloth 54 and the lower force cloths 50, 52 may be configured to be equally difficult to stretch.

In addition, in the above embodiment, the upper force cloth 54 is configured to include a front upper force cloth 54A and a rear upper force cloth 54B, but this is not limited to this. For example, the upper force cloth 54 may be configured to include only the front upper force cloth 54A.

In addition, in the above embodiment, the other end of each of the front upper force cloth 54A and the rear upper force cloth 54B is fixed to the upper frame 20B, but this is not limited to the above. For example, the other end of the rear upper force cloth 54B may be fixed (sewn) to the seat back skin 24 on the rear side of the seat back 16.

In addition, in the above embodiment, the torso chamber 42B of the side airbag 42 is configured to be large enough to restrain the occupant P from the chest to the waist, but this is not limited thereto, and the size of the torso chamber 42B can be changed as appropriate.

The present invention can be modified in various ways without departing from the spirit of the invention. It goes without saying that the scope of the invention is not limited to the above embodiment.

10 Vehicle seat equipped with side airbag device 12 Seat body 16 Seat back 16R Side portion 16S Shoulder portion 16U Upper end portion 24 Seat back skin (skin)
32 Three-point seat belt 32A Shoulder belt 42 Side airbag 42A Head chamber 42B Torso chamber 44 Inflator 50, 52 Lower webbing 54 Upper webbing P Occupant H Head B Torso

Claims (4)

A seat body in which an occupant is restrained using a three-point seat belt;
an inflator that generates gas when a side collision of the vehicle is detected or predicted;
a side airbag that is stored in a folded state along an upper end portion of a seat back of the seat body from a side portion on an outer side in a vehicle width direction through a shoulder, a torso chamber that is supplied with gas from the inflator inflates and deploys from the side portion between the torso of the occupant and a vehicle body side portion, and a head chamber that is supplied with gas via the torso chamber inflates and deploys from the upper end portion between the head of the occupant and a shoulder belt of the seat belt;
a lower webbing that connects a skin of the seat back and a side frame at the side and transmits an inflation pressure of the torso chamber to the skin to split the skin;
an upper webbing that connects an upper surface of the seat back and an upper frame at the upper end and transmits an inflation pressure of the head chamber to the upper surface to split the upper surface;
A vehicle seat equipped with a side airbag device. A vehicle seat equipped with a side airbag device as described in claim 1, in which one end of the upper webbing is sewn together with a tear seam provided on the skin, and the other end is fixed to the upper frame. A vehicle seat equipped with a side airbag device as described in claim 2, wherein the upper webbing is looped so as to surround the head chamber housed in the upper end of the seat back. 4. The vehicle seat equipped with a side airbag device according to claim 1, wherein the upper webbing is configured to be less stretchable than the lower webbing.