Patent Description:
Far-side airbag devices such as that disclosed in Japanese Patent Application Laid-Open (<CIT> are known. Such a far-side airbag device includes a first chamber that deploys toward an adjacent seatback from one side section of a seatback on the opposite side to a shoulder belt in an oblique side-on collision or a side-on collision of a vehicle, a second chamber that receives gas supplied from a front end portion of the first chamber so as to deploy toward a seat front side, and a third chamber that receives gas supplied from a front end portion of the second chamber so as to deploy toward a seat width direction inside. The far-side airbag device also includes a tether that couples the first chamber and the third chamber together.

However, since such a far-side airbag device is an airbag device that only deploys on one side, namely a fixed point (base section) of its airbag is only present on one side of the seatback, the airbag attempts to rotate in a direction away from the head of an occupant centered on the fixed point in plan view while the head of the occupant is being restrained during the latter half of a collision.

The likelihood of the head of the occupant incurring a rotational injury increases as a result. Moreover, since space at the side (alongside the side section) of the seatback is limited, sufficient deployment space for the airbag cannot be secured, such that airbag deployment performance is negatively affected, for example airbag deployment may be delayed.

<CIT> discloses a vehicle seat comprising a shoulder belt and a vehicle airbag device, comprising an airbag body including: a front-rear chamber configured to pass a side of a head of an occupant seated in the vehicle seat and to deploy toward a seat front side as a result of gas being ejected from an inflator actuated in a case in which a head-on collision of a vehicle is detected or predicted, so as to be disposed at the side of the head of the occupant having a leading end chamber configured to deploy toward a seat width direction inner side from a seat front side end portion of the front-rear chamber so as to be disposed at the seat front side of the head of the occupant.

The present disclosure obtains a vehicle seat comprising a vehicle airbag device that enables an airbag body to be deployed at an early stage, and also enables the likelihood of the head of an occupant incurring a rotational injury to be reduced.

A vehicle seat of a first aspect, according to claim <NUM>, includes an airbag body. The airbag body includes a front-rear chamber, a leading end chamber, and a shoulder-contact section. The front-rear chamber is configured to pass a side of the head of an occupant seated in a vehicle seat and to deploy toward a seat front side as a result of gas being ejected from an inflator actuated in a case in which a head-on collision of a vehicle is detected or predicted, so as to be disposed at the side of the head of the occupant. The leading end chamber is configured to deploy toward a seat width direction inner side from a seat front side end portion of the front-rear chamber so as to be disposed at the seat front side of the head of the occupant. The shoulder-contact section is configured to contact, from the seat front side, a first shoulder of the occupant so as to restrain the first shoulder, the first shoulder being at an opposite side from a second shoulder of the occupant across which a shoulder belt is worn.

In the first aspect, in a case in which the inflator is actuated in a vehicle head-on collision, the front-rear chamber of the airbag body passes the side of the head of the occupant seated in the vehicle seat and deploys toward the seat front side so as to be disposed at the side of the head of the occupant. Then, the leading end chamber of the airbag body deploys toward the seat width direction inner side from the seat front side end portion of the front-rear chamber so as to be disposed at the seat front side of the head of the occupant and to restrain the head of the occupant. Note that there is more space at the side of the head of the occupant than at a side (alongside a side section) of a seatback. Thus, there is less of a limit on space than when an airbag deploys toward the seat front side from the side section of the seatback, such that the airbag body is deployed at an early stage.

Moreover, the shoulder-contact section of the airbag body contacts the other shoulder on the opposite side to the second shoulder of the occupant, across which the shoulder belt is worn, from the seat front side, so as to restrain the other shoulder of the occupant. Note that, accompanying forward movement of the occupant in a vehicle head-on collision, the second shoulder restrained by the shoulder belt bears load from the shoulder belt, such that the head and the other shoulder attempt to rotate about an axis with its rotation axial direction in the vertical direction. However, when this occurs, the other shoulder bears load from the airbag body through the shoulder-contact section, such that the head and the other shoulder attempt to rotate in the opposite direction. This enables rotation of the head to be cancelled out, such that the likelihood of the head of the occupant incurring a rotational injury in a vehicle head-on collision is reduced.

Further, in the vehicle seat of the first aspect, the shoulder-contact section includes a first shoulder-restraining face configured to extend toward a seat lower side from a lower end portion of the front-rear chamber.

The shoulder-contact section includes the first shoulder-restraining face that extends toward the seat lower side from the lower end portion of the front-rear chamber of the airbag body. Note that the front-rear chamber is deployed prior to the leading end chamber. Thus, the shoulder-contact section is deployed at an early stage during a vehicle head-on collision. Thus, the likelihood of the head of the occupant incurring a rotational injury is effectively reduced. Moreover, the airbag body is struck by the shoulder of the occupant, such that contact force against the head of the occupant is alleviated. Thus, torsion force arising at the neck of the occupant is also reduced.

A vehicle seat of a third aspect is the vehicle seat of the first aspect, wherein the airbag body includes a ceiling-abutment section configured to abut a ceiling of a vehicle cabin.

In the third aspect, when the shoulder of the forward-moving occupant abuts the shoulder-contact section of the airbag body in a vehicle head-on collision, a boundary section between the front-rear chamber and the leading end chamber of the airbag body in side view attempts to rotate in a direction approaching the ceiling. When this occurs, the ceiling-abutment section of the airbag body abuts the ceiling and bears reaction force from the ceiling, such that rotation of the airbag body is suppressed, the airbag body is suppressed from riding up toward the upper-front side, and the chest of the occupant is suppressed from pivoting toward the lower side. This suppresses any change to a relative positional relationship between the head and the chest of the occupant, such that an injury severity score for the neck of the occupant is reduced.

A vehicle seat of a fourth aspect is the vehicle seat of the third aspect, wherein the ceiling-abutment section is configured by a first projecting section configured to extend toward a seat upper side from an upper end portion of the front-rear chamber at a location corresponding to the shoulder-contact section.

In the fourth aspect, since the ceiling-abutment section is provided as the first projecting section at the upper end portion of the front-rear chamber at the location corresponding to the shoulder-contact section of the front-rear chamber that deploys initially, the ceiling-abutment section is deployed at an early stage. Moreover, since the shoulder-contact section and the ceiling-abutment section are provided with a corresponding positional relationship, the airbag body is effectively suppressed from riding up toward the upper-front side and the chest of the occupant is effectively suppressed from pivoting toward the lower side.

A vehicle seat of a fifth aspect is the vehicle seat of the third aspect or the fourth aspect, wherein the airbag body includes an auxiliary shoulder-contact section configured to contact the second shoulder of the occupant from the seat front side so as to restrain the second shoulder of the occupant.

In the fifth aspect, the auxiliary shoulder-contact section of the airbag body contacts the second shoulder of the occupant across which the shoulder belt is worn from the seat front side so as to restrain the second shoulder of the occupant. Thus, restraint of the occupant by the shoulder belt is effectively assisted in a vehicle head-on collision.

A vehicle seat of a sixth aspect is the vehicle seat of the fifth aspect, wherein the auxiliary shoulder-contact section includes a second shoulder-restraining face configured to extend toward a seat lower side from a lower end portion of the leading end chamber.

In the sixth aspect, the auxiliary shoulder-contact section includes the second shoulder-restraining face that extends toward the seat lower side from the lower end portion of the leading end chamber of the airbag body. Thus, the airbag body is struck by the other shoulder of the occupant and the second shoulder of the occupant with a good balance, such that contact force against the head of the occupant is alleviated. Torsion force occurring at the neck of the occupant is thereby reduced.

A vehicle seat of a seventh aspect is the vehicle seat of the fifth aspect or the sixth aspect, wherein the ceiling-abutment section is configured by a second projecting section configured to extend toward a seat upper side from an upper end portion of the leading end chamber at a location corresponding to the auxiliary shoulder-contact section.

In the seventh aspect, the ceiling-abutment section is provided as the second projecting section at the upper end portion of the leading end chamber at the location corresponding to the auxiliary shoulder-contact section of the leading end chamber. Namely, the auxiliary shoulder-contact section and the ceiling-abutment section are provided with a corresponding positional relationship. Thus, the airbag body is effectively suppressed from riding up toward the upper-front side and the chest of the occupant is effectively suppressed from pivoting toward the lower side.

A vehicle seat of an eighth aspect is the vehicle seat of the third aspect, wherein the ceiling-abutment section is configured by a third projecting section configured to extend toward a seat upper side from an upper end portion of a boundary section between the front-rear chamber and the leading end chamber.

In the eighth aspect, the ceiling-abutment section is provided as the third projecting section at the upper end portion of the boundary section between the front-rear chamber and the leading end chamber. Thus, the airbag body is effectively suppressed from riding up toward the upper-front side and the chest of the occupant is effectively suppressed from pivoting toward the lower side.

A vehicle seat of a ninth aspect is the vehicle seat of any one of the first aspect to the eighth aspect, wherein the front-rear chamber and the leading end chamber of the airbag body form a "V" shape in plan view. A head-restraining face of the leading end chamber, which is configured to restrain the head of the occupant, is set at an acute angle with respect to a central axis line of the front-rear chamber.

In the ninth aspect, the airbag body that forms a "V" shape in plan view covers so as to surround the head of the forward-moving occupant in a vehicle head-on collision. Namely, since the head-restraining face of the leading end chamber is set at an angle of inclination that is an acute angle, a rotation-inducing moment in the opposite direction to a direction away from the head of the occupant can be generated in the airbag body, thereby enabling the airbag body to be made to rotate toward the head of the occupant (in the opposite direction to the direction away from the head). The head of the occupant is effectively suppressed from rotating, and the head of the occupant is effectively restrained as a result.

A vehicle seat of a tenth aspect is the vehicle seat of any one of the first aspect to the ninth aspect, wherein the vehicle seat includes a case in which the airbag body is accommodated, the case including a lid configured to open when the airbag body is deployed. The lid is provided at a position that has left-right symmetry relative to a position of a belt guide, configured to guide the shoulder belt at a position corresponding to the second shoulder of the occupant, with respect to a center line of the vehicle seat.

In the tenth aspect, the vehicle seat includes the case in which the airbag body is accommodated, the case including the lid that opens when the airbag body is deployed. The lid is provided at a position that has left-right symmetry relative to the position of the belt guide, configured to guide the shoulder belt at a position corresponding to the second shoulder of the occupant, with respect to the center line of the vehicle seat. This improves the left-right balance of the vehicle seat to give a more favorable appearance. Note that in the present disclosure, "left-right symmetry" refers not only to exact left-right symmetry, but also includes cases in which there is substantially left-right symmetry with slight misalignment from exactly symmetrical positions.

As described above, the present disclosure enables the airbag body to be deployed at an early stage, and also enables the likelihood of the head of the occupant incurring a rotational injury to be reduced.

Exemplary embodiments of the present invention will be described in detail based on the following figures, wherein:.

Detailed explanation follows regarding exemplary embodiments according to the present disclosure, with reference to the drawings. Note that to aid explanation, in the drawings, the arrow UP indicates a seat upward direction, the arrow FR indicates a seat forward direction, and the arrow RH indicates a seat right-hand direction as appropriate. Thus, in the following explanation, unless specifically stated otherwise, reference to vertical, front-rear, and left-right directions refers to vertical, front-rear, and left-right directions of a vehicle seat <NUM>. Moreover, the left-right direction corresponds to a seat width direction.

A vehicle airbag device (hereafter simply referred to as "airbag device") <NUM> according to the present exemplary embodiment is provided at the rear side of a headrest <NUM> (described later) of the vehicle seat <NUM>, which is principally employed as rear seating in a vehicle. Although an example is described in which the vehicle seat <NUM> of the present exemplary embodiment is applied as a right-hand seat (seat width direction outside seat) of the rear seating, the airbag device <NUM> may be provided to a front seat. As an example, in the present exemplary embodiment, an "occupant P" is an occupant equivalent to a <NUM>th percentile adult male (AM50) dummy.

First, explanation follows regarding the airbag device <NUM> according to a first exemplary embodiment. As illustrated in <FIG> and <FIG>, the vehicle seat <NUM> includes a seat cushion (not illustrated in the drawings) on which the occupant P sits (which supports the buttocks and thighs of the occupant P), a seatback <NUM> that supports the back of the occupant P, and the headrest <NUM> that supports the head Ph of the occupant P.

A retractor <NUM>, serving as a take-up device that takes up a seatbelt <NUM>, is embedded in an upper section on the right side (one left-right direction side) of the seatback <NUM>. A slit-shaped belt opening 12A for pulling the seatbelt <NUM> fed out from the retractor <NUM> toward the seat front side is formed in an upper end face on the right side of the seatback <NUM>. A belt guide <NUM> that guides the seatbelt <NUM> is provided at a peripheral edge of the belt opening 12A.

A pre-tensioner mechanism is inbuilt in the retractor <NUM>. In a vehicle head-on collision, the retractor <NUM> instantaneously takes up the seatbelt <NUM> so as to limit movement of the occupant P toward the front side due to force under inertia. Thus, the seatbelt device of the present exemplary embodiment is a pre-tensioner seatbelt device.

As illustrated in <FIG>, a tongue plate <NUM> is attached to the seatbelt <NUM> so as to be capable of sliding. The tongue plate <NUM> is configured to as be capable of being detachably fitted into a buckle <NUM> provided on the left side (other left-right direction side) of the seat cushion. Note that in the following explanation, a part of the seatbelt <NUM> worn across a shoulder Ps of the occupant P is referred to as a shoulder belt <NUM>.

As illustrated in <FIG> and <FIG>, the headrest <NUM> is provided at the seat width direction center of an upper end portion of the seatback <NUM> so as to be capable of being raised and lowered. A case <NUM> in the form of casing that is longer in the seat width direction than headrest <NUM> is provided at the rear side of the headrest <NUM>. Note that, with the exception of a front wall <NUM> of a side section <NUM>, described later, the case <NUM> is covered by a similar covering to a covering that covers the headrest <NUM>. However, this covering and a corresponding part of the case <NUM> is omitted from illustration in the drawings.

A predetermined space S (including a placement area S1 and a stowing area S2, described later) is formed inside the case <NUM>. An inflator <NUM> is disposed in the placement area S1, serving as a part of the space S formed at the seat width direction center of the case <NUM>. The inflator <NUM> is formed in a substantially circular cylindrical shape. An outer peripheral portion of the inflator <NUM> is supported by a reaction force-withstanding plate <NUM> formed as casing through a retainer <NUM>, such that an axial center portion of the inflator <NUM> is disposed along the seat width direction.

The reaction force-withstanding plate <NUM> is for example fixed to a seatback frame (not illustrated in the drawings) through a bracket (not illustrated in the drawings) penetrating a bottom wall 22D of the case <NUM>. The reaction force-withstanding plate <NUM> is configured so as to be able to withstand reaction force transmitted from an airbag body <NUM> (described later) through the inflator <NUM> when the airbag body <NUM> deploys toward the front side. Note that the reaction force-withstanding plate <NUM> and the retainer <NUM> are also disposed inside the placement area S <NUM>.

The inflator <NUM> is electrically connected to an airbag ECU (not illustrated in the drawings) provided to the vehicle. The airbag ECU is electrically connected to a detection device (not illustrated in the drawings) including a collision detection sensor (acceleration sensor) and so on provided to the vehicle. Thus, in a case in which a vehicle head-on collision is detected by the detection device, the inflator <NUM> is actuated through the airbag ECU so as to instantaneously eject gas.

Note that instead of being configured so as to actuate when a vehicle head-on collision is detected, the inflator <NUM> may be configured so as to actuate when a vehicle head-on collision is predicted by a detection device including a collision prediction sensor (not illustrated in the drawings) and so on. A connection portion (not illustrated in the drawings) of the airbag body <NUM> is fitted into and connected to an ejection outlet 28A of the inflator <NUM>.

The left side (seat width direction inside) of the case <NUM> is configured by the side section <NUM> that has a rectangular case shape and juts out further toward the left side than a left-side end face <NUM> of the headrest <NUM> in face-on view. The airbag body <NUM> of the airbag device <NUM> is stowed in a rolled-up state (outward rolled state) in the stowing area S2 formed in the side section <NUM> and configuring the remaining area of the space S.

Note that in order to simplify the drawing, the rolled-up shape of the airbag body <NUM> is omitted in <FIG>. Moreover, in the following explanation, a section of the airbag body <NUM> that remains housed in the side section <NUM> of the airbag body <NUM> (a section that does not project out from the side section <NUM>; see <FIG>) is referred to as a base section 32A, and a connection section of the airbag body <NUM> that is connected to the ejection outlet 28A of the inflator <NUM> is referred to as a fixed point 32B (see <FIG>).

As illustrated in <FIG>, the airbag device <NUM> includes the airbag body <NUM> that deploys when gas is ejected from the inflator <NUM> by passing the left side of the head Ph of the occupant P seated in the vehicle seat <NUM> and unraveling from its rolled shape toward the front side. Note that the left side of the head Ph of the occupant P seated in the vehicle seat <NUM> refers to a space at a position that has substantially left-right symmetry relative to a position of the belt guide <NUM> of the shoulder belt <NUM> on the opposite side of the headrest <NUM> (the head Ph of the occupant P) (namely, with respect to a center line of the vehicle seat).

As illustrated in <FIG> and <FIG>, the airbag body <NUM> includes a front-rear chamber <NUM> disposed at one side (the left side in the present exemplary embodiment) of the head Ph of the occupant P, and a leading end chamber <NUM> that deploys toward the seat width direction inner side from a front side end portion of the front-rear chamber <NUM> so as to be disposed at the front side (the front-right side in the present exemplary embodiment) of the head Ph (face) of the occupant P.

The airbag body <NUM> also includes a belt-shaped tether <NUM> that couples between a predetermined position at an upper end portion of the front-rear chamber <NUM> and a predetermined position at an upper end portion of the leading end chamber <NUM>. Namely, the airbag body <NUM> is deployed in a state bent into a substantially "V" shape in plan view, and with the exception of a shoulder-contact section <NUM> (extension section 34A), described later, airbag body <NUM> is disposed at the upper side of the shoulders Ps of the occupant P so as to be capable of restraining at least the head Ph of the occupant P.

Note that although it is sufficient that the tether <NUM> is provided so as to couple between at least the upper end portion of the front-rear chamber <NUM> and the upper end portion of the leading end chamber <NUM>, another tether may for example be provided so as to couple between a predetermined position at a lower end portion of the front-rear chamber <NUM> and a predetermined position at a lower end portion of the leading end chamber <NUM>. The tether <NUM> is only illustrated in <FIG>, and is omitted from illustration in <FIG>, <FIG>, and <FIG>, described later.

Explanation follows regarding an angle of inclination θ of the leading end chamber <NUM> with respect to the front-rear chamber <NUM> and a rotation-inducing moment acting on the airbag body <NUM>, with respect to <FIG> and <FIG>. In plan view, a seat width direction central line running through the front-rear chamber <NUM> in the front-rear direction is referred to as a central axis line 34C, and a face of the leading end chamber <NUM> that opposes the head Ph is referred to as a head-restraining face 36B. As illustrated in <FIG>, the angle of inclination θ of the head-restraining face 36B of the leading end chamber <NUM> with respect to the central axis line 34C of the front-rear chamber <NUM> is set as an acute angle (preferably between <NUM>° and <NUM>°).

In a case in which the head Ph of the occupant P contacts the head-restraining face 36B of the leading end chamber <NUM> and a head-restraining face 34B, this being a face of the front-rear chamber that opposes the head Ph, under force due to inertia generated in a vehicle head-on collision, load is input to the head-restraining face 34B and the head-restraining face 36B from the head Ph. If a load F input to the head-restraining face 36B is considered out of the load input to the head-restraining face 34B and the head-restraining face 36B, this load F can be broken down into a load F1 input along the head-restraining face 36B, and a load F2 input in a direction normal to the head-restraining face 36B.

There is sufficient friction between the head Ph of the occupant P and the head-restraining face 36B that the head Ph does not slide along the head-restraining face 36B. Thus, the load F1 is cancelled out by this friction force between the head Ph and the head-restraining face 36B. The load F2 input in a direction normal to the head-restraining face 36B can be broken down into a load F3 along the front-rear direction, and a load F4 along the seat width direction (left-right direction).

Note that a distance along the front-rear direction from the fixed point 32B at the base section 32A of the airbag body <NUM> to a contact point T where the head Ph of the occupant P contacts the head-restraining face 36B is referred to as a distance L1, and a shortest distance from the central axis line 34C of the front-rear chamber <NUM> to the contact point T is referred to as a distance L2. When the head Ph of the occupant P contacts the head-restraining face 36B of the leading end chamber <NUM>, a rotation-inducing moment M1 (M1 = F3 × L2) that causes the airbag body <NUM> to rotate in a direction away from the occupant P occurs at the fixed point 32B of the airbag body <NUM>.

However, since the head-restraining face 36B of the leading end chamber <NUM> is set at the angle of inclination θ, this being an acute angle with respect to the central axis line 34C of the front-rear chamber <NUM> as described above, a rotation-inducing moment M2 (M2 = F4 × L1) that causes the airbag body <NUM> to rotate in the opposite direction to the rotation-inducing moment M1 can be generated at the fixed point 32B.

Namely, in this airbag body <NUM>, the airbag body <NUM> can be made to rotate toward the head Ph side of the occupant P (in the opposite direction to the direction away from the head Ph). Note that as illustrated in <FIG>, the angle of inclination θ of the head-restraining face 36B of the leading end chamber <NUM> with respect to the central axis line 34C of the front-rear chamber <NUM> is preferably set to <NUM>°, at which the rotation-inducing moment M2 is at a maximum.

As illustrated in <FIG> and <FIG>, the airbag body <NUM> includes the shoulder-contact section <NUM> that contacts from the front side the left side (other side) shoulder PsL of the occupant P on the opposite side in the left-right direction to the right side (one side) shoulder PsR across which the shoulder belt <NUM> is worn so as to restrain the left shoulder PsL of the occupant P by relatively pressing the left shoulder PsL toward the seatback <NUM>.

The shoulder-contact section <NUM> is configured by a rear face of the extension section 34A that has a substantially triangular conical shape extending integrally toward the lower side from a lower end portion (lower end face) on the base section 32A side of the front-rear chamber <NUM> when the front-rear chamber <NUM> has been inflated and deployed. This rear face configures a planar-shaped first shoulder-restraining face <NUM>. The shoulder-contact section <NUM> abuts the left shoulder PsL of the occupant P from the front side directly after the front-rear chamber <NUM> has been deployed (prior to completing deployment of the leading end chamber <NUM>), such that the shoulder PsL of the occupant P is restrained by the seatback <NUM>.

Thus, as illustrated in <FIG>, in a case in which the vehicle is in a head-on collision, first, the right shoulder PsR of the occupant P is pressed from the front side by the shoulder belt <NUM>, after which the left shoulder PsL of the occupant P is pressed from the front side by the shoulder-contact section <NUM> formed to the front-rear chamber of the deployed airbag body <NUM>.

Then, when inflation and deployment of the airbag body <NUM> is complete, the shoulder-contact section <NUM> integrally formed to the base section 32A side of the front-rear chamber <NUM> abuts the left shoulder PsL of the occupant P from the front side, such that a boundary section <NUM> (bent-back section) between the front-rear chamber <NUM> and the leading end chamber <NUM> is retained at the front side of the head Ph of the occupant P.

Namely, the front-rear chamber <NUM> extends further toward the front side at a deployment direction downstream side of the shoulder-contact section <NUM> than at a deployment direction upstream side of the shoulder-contact section <NUM>, such that a gap D is formed between the head Ph (face) of the occupant P and the front-rear chamber <NUM>, the leading end chamber <NUM>, and the boundary section <NUM> (see <FIG>, <FIG>, <FIG>, and <FIG>). Thus, the airbag body <NUM> is configured so as not to contact the face of the occupant P as long as the occupant P does not move greatly toward the front side under force due to inertia.

The front wall <NUM>, serving as a lid configuring a front end face of the side section <NUM> of the case <NUM>, is for example configured so as to split in a straight line along the vertical direction accompanying deployment of the airbag body <NUM>. Note that the split location is preferably at a right end portion (seat width direction inside end portion) of the front wall <NUM>. In other words, a weakened portion or the like that splits easily is preferably formed at the right end portion of the front wall <NUM>.

When the split location is at the right end portion of the front wall <NUM> (when a weakened portion or the like that splits easily is formed at the right end portion of the front wall <NUM>), the front wall <NUM> opens with a left end portion serving as a hinge portion, thereby enabling the deploying airbag body <NUM> to be suppressed or prevented from contacting the head of an occupant (not illustrated in the drawings) seated at the center of the rear seating. Note that the front wall <NUM> is disposed at a position that has substantially left-right symmetry relative to the position of the belt guide <NUM> on the other side of the headrest <NUM> (head Ph of the occupant P) (namely, with respect to the center line of the vehicle seat).

As illustrated in <FIG>, in a state unfilled with gas, three non-inflating portions <NUM> that extend along the vertical direction are formed by stitching at predetermined intervals in the vertical direction at a substantially front-rear direction central portion of the airbag body <NUM>. Each of the non-inflating portions <NUM> is formed in a substantially elliptical shape with its length direction along the vertical direction.

As a result of forming the respective non-inflating portions <NUM>, the leading end chamber <NUM> is capable of bending toward the seat width direction inside with respect to the front-rear chamber <NUM>, and is capable of deploying toward the seat width direction inside. Namely, a section of the airbag body <NUM> further toward the deployment direction upstream side than the non-inflating portions <NUM> configures the front-rear chamber <NUM>, whereas a section further toward the deployment direction downstream side than the non-inflating portions <NUM> configures the leading end chamber <NUM>.

Next, explanation follows regarding operation of the airbag device <NUM> according to the first exemplary embodiment configured as described above.

In a case in which the detection device detects that the vehicle is involved in a head-on collision, the inflator <NUM> is actuated such that gas is instantaneously ejected into the airbag body <NUM>. When gas is ejected into the airbag body <NUM>, the front wall <NUM> of the side section <NUM> splits as a result of the airbag body <NUM> being deployed (as a result of being pressed from the inside by the airbag body <NUM>). The airbag body <NUM> then passes the left side of the head Ph of the occupant P and deploys toward the front side from the side section <NUM>.

More specifically, in a case in which the inflator <NUM> is actuated in a vehicle head-on collision, the front-rear chamber <NUM> of the airbag body <NUM> passes the left side of the head Ph of the occupant P and deploys toward the front side so as to be disposed at the left side of the head Ph of the occupant P. Then, the leading end chamber <NUM> of the airbag body <NUM> deploys toward the seat width direction inner side from a seat front side end portion of the front-rear chamber <NUM> so as to be disposed at the front-right side of the head Ph (face) of the occupant P.

At least the head Ph of the occupant P seated in the vehicle seat <NUM> and attempting to move toward the front side under force due to inertia is restrained by the airbag body <NUM> (front-rear chamber <NUM> and leading end chamber <NUM>) disposed in this manner. Namely, even if the head Ph of the occupant P moves greatly toward the front side under force due to inertia, the head Ph can be restrained by the airbag body <NUM> (front-rear chamber <NUM> and leading end chamber <NUM>).

Moreover, since the head-restraining face 36B of the leading end chamber <NUM> is set at the angle of inclination θ (such as θ = <NUM>°) that is an acute angle with respect to the central axis line 34C of the front-rear chamber <NUM>, the rotation-inducing moment M2 that causes the airbag body <NUM> to rotate in the opposite direction to the rotation-inducing moment M1 can be generated at the fixed point 32B.

Namely, in this airbag body <NUM>, the airbag body <NUM> can be made to rotate toward the head Ph of the occupant P (in the opposite direction to the direction away from the head Ph). Thus, in a vehicle head-on collision, the head Ph of the occupant P attempting to move toward the front side under force due to inertia can be covered so as to be surrounded by the airbag body <NUM>, thereby enabling ineffectual restraint of the head Ph to be suppressed or prevented.

Moreover, there is more space at the side of the head Ph of the occupant P than at the side (alongside a side section) of the seatback <NUM>. Thus, there is less of a limit on space than when an airbag (not illustrated in the drawings) is deployed toward the front side from the side section of the seatback <NUM>, thereby enabling the airbag body <NUM> (front-rear chamber <NUM> and leading end chamber <NUM>) to be deployed at an early stage.

Moreover, the side where the airbag body <NUM> is deployed is the opposite side in the left-right direction to the belt guide <NUM> (belt opening 12A), such that deployment of the airbag body <NUM> is unaffected by the shoulder belt <NUM>. Thus, the airbag device <NUM> according to the present exemplary embodiment can easily be applied not only to the rear seating of the vehicle, but also to a front seat.

Moreover, directly after the front-rear chamber <NUM> has deployed (prior to completion of deployment of the leading end chamber <NUM>), the shoulder-contact section <NUM> of the airbag body <NUM> contacts from the front side the left shoulder PsL on the opposite side in the left-right direction to the right shoulder PsR of the occupant P across which the shoulder belt <NUM> is worn, such that the left shoulder PsL of the occupant P is relatively pressed toward the seatback <NUM> and thereby restrained.

Note that, accompanying forward movement of the occupant P in a vehicle head-on collision, the right shoulder PsR restrained by the shoulder belt <NUM> bears load from the shoulder belt <NUM>, such that the head Ph and left shoulder PsL of the occupant P attempt to rotate about an axis with its rotation axial direction in the vertical direction. Namely, the head Ph and left shoulder PsL of the occupant P attempt in rotate in a clockwise direction in plan view.

However, when this occurs, the left shoulder PsL of the occupant P bears load toward the rear side from the airbag body <NUM> (at least the front-rear chamber <NUM>) through the shoulder-contact section <NUM>, such that the head Ph and left shoulder PsL of the occupant P are effectively made to rotate in the opposite direction (in a counterclockwise direction in plan view). This enables rotational forces applied to the head Ph of the occupant P to cancel each other out.

Namely, involuntary rotation of the head Ph of the occupant P can be effectively suppressed, thereby enabling the head Ph of the occupant P to be effectively restrained. This enables the likelihood of the head of the occupant P incurring a rotational injury to be reduced, and enables torsion force arising at the neck Pn of the occupant P to be reduced, in a vehicle head-on collision.

Moreover, the shoulder-contact section <NUM> includes the first shoulder-restraining face <NUM> that extends toward the lower side from the lower end portion (lower end face) of the front-rear chamber <NUM> of the airbag body <NUM>. Note that the front-rear chamber <NUM> is deployed prior to the leading end chamber <NUM>. This enables the shoulder-contact section <NUM> to be deployed at an early stage, such that the likelihood of the head of the occupant P incurring a rotational injury can be even more effectively reduced in a vehicle head-on collision.

Moreover, the shoulder-contact section <NUM> (first shoulder-restraining face <NUM>) only contacts a front surface of the left shoulder PsL of the occupant P and does not press the left arm of the occupant P. This enables the occupant P to be restrained with a good left-right balance by the shoulder-contact section <NUM> together with the shoulder belt <NUM> that contacts a front surface of the right shoulder PsR of the occupant P so as to restrain the shoulder PsR.

Thus, even if the head Ph of the occupant P moves toward the front side under force due to inertia, a contact force with which the head Ph of the occupant P contacts the airbag body <NUM> can be alleviated. Namely, a situation in which the head Ph (face) of the occupant P violently strikes the airbag body <NUM> can be avoided. This enables torsion force arising at the neck Pn of the occupant P to be even more effectively reduced.

As described above, the front wall <NUM> is configured to open with the left end portion acting as a hinge portion when the airbag body <NUM> is deployed. Thus, the deploying airbag body <NUM> can be suppressed or prevented by the front wall <NUM> from contacting the head (face) of an occupant (not illustrated in the drawings) seated in the central vehicle seat (not illustrated in the drawings) of the rear seating.

Moreover, the front wall <NUM> that opens when the airbag body <NUM> is deployed is provided at a position that has substantially left-right symmetry relative to the position of the belt guide <NUM>, which guides the shoulder belt <NUM> at a position corresponding to the right shoulder PsR of the occupant P, on the other side of the headrest <NUM> (head Ph of the occupant P) (namely, with respect to the center line of the vehicle seat). As illustrated in <FIG>, this improves the left-right balance of the vehicle seat <NUM> to give a more favorable appearance.

Next, explanation follows regarding an airbag device <NUM> according to a second exemplary embodiment. Note that locations that are equivalent to those in the first exemplary embodiment are allocated the same reference numerals, and detailed explanation thereof (including common operation) is omitted as appropriate.

As illustrated in <FIG> and <FIG>, the airbag body <NUM> of the airbag device <NUM> according to the second exemplary embodiment only differs from the first exemplary embodiment in the respect that it includes a ceiling-abutment section <NUM> that abuts a ceiling <NUM> of the vehicle cabin.

The ceiling-abutment section <NUM> is preferably formed in a block shape on the base section 32A side of the front-rear chamber <NUM> so as to hit the ceiling <NUM> as early as possible when the front-rear chamber <NUM> is inflated and deployed. In the present exemplary embodiment, the ceiling-abutment section <NUM> is configured of a substantially elliptical column-shaped first projecting section <NUM> that extends integrally toward the upper side from an upper end portion (upper end face) of the front-rear chamber <NUM> at a location corresponding to the shoulder-contact section <NUM>.

More specifically, as illustrated in <FIG>, the shoulder-contact section <NUM> and the first projecting section <NUM> are formed at substantially the same position in the front-rear direction (the deployment direction of the front-rear chamber <NUM>). In other words, as illustrated in <FIG>, the first projecting section <NUM> is formed at a position where at least a part thereof overlaps the shoulder-contact section <NUM> in plan view.

As illustrated in <FIG>, a situation in which the left shoulder PsL of the forward-moving occupant P strikes the shoulder-contact section <NUM> in a vehicle head-on collision, such that the airbag body <NUM> is pressed forward (so as to shift from the state illustrated by phantom lines to the state illustrated by solid lines), and the boundary section <NUM> of the airbag body <NUM> attempts to rotate toward the upper side with the base section 32A of the airbag body <NUM> as a center of rotation in side view viewed along the vehicle width direction (seat width direction), can be suppressed or prevented by the ceiling-abutment section <NUM> (first projecting section <NUM>).

Namely, as illustrated by the solid lines in <FIG>, an upper end face 46A of the first projecting section <NUM> abuts the ceiling <NUM>, such that the first projecting section <NUM> (ceiling-abutment section <NUM>) bears reaction force from the ceiling <NUM>. This suppresses rotation toward the upper side with the base section 32A side of the airbag body <NUM> as a center of rotation, thereby enabling the boundary section <NUM> of the airbag body <NUM> to be suppressed from riding up toward the upper-front side, and the chest of the occupant P to be suppressed from pivoting toward the lower side.

This enables a change to a relative positional relationship between the head Ph and the chest of the occupant P to be suppressed, thereby enabling the likelihood of the head of the occupant P incurring a rotational injury to be reduced and enabling an injury severity score for the neck Pn of the occupant P (torsion force arising at the neck Pn) to be reduced, in a vehicle head-on collision.

Thus, even if the head Ph of the occupant P moves greatly toward the front side under force due to inertia in a vehicle head-on collision as illustrated in the example in <FIG>, the head Ph of the occupant P can be effectively restrained by the airbag body <NUM> (front-rear chamber <NUM> and leading end chamber <NUM>) without the airbag body <NUM> dislodging toward the upper side away from the head Ph of the occupant P.

Next, explanation follows regarding an airbag device <NUM> according to a third exemplary embodiment. Note that locations that are equivalent to those in the first exemplary embodiment or second exemplary embodiment are allocated the same reference numerals, and detailed explanation thereof (including common operation) is omitted as appropriate.

As illustrated in <FIG> and <FIG>, the airbag body <NUM> of the airbag device <NUM> according to the third exemplary embodiment only differs from the second exemplary embodiment in the respect that it includes an auxiliary shoulder-contact section <NUM> that contacts the right shoulder PsR of the occupant P from the front side so as to restrain the right shoulder PsR of the occupant P, and that a ceiling-abutment section <NUM> that abuts the ceiling <NUM> of the vehicle cabin is integrally formed to an upper end portion of the leading end chamber <NUM>.

The auxiliary shoulder-contact section <NUM> is configured by a rear face of a substantially triangular conical-shaped extension section 36A (see <FIG>) that extends integrally toward the lower side from a lower end portion (lower end face) of a leading end section <NUM> (a rear end section in a state bent into a substantially "V" shape in plan view) side of the leading end chamber <NUM> when the leading end chamber <NUM> has been inflated and deployed. This rear face configures a planar-shaped second shoulder-restraining face <NUM>.

The auxiliary shoulder-contact section <NUM> abuts the right shoulder PsR of the occupant P from the front side directly after the leading end chamber <NUM> has deployed, such that the shoulder PsR of the occupant P is restrained by the seatback <NUM>. Namely, the auxiliary shoulder-contact section <NUM> (second shoulder-restraining face <NUM>) only contacts the front surface of the right shoulder PsR of the occupant P without pressing against the right arm of the occupant P. Thus, the auxiliary shoulder-contact section <NUM> effectively assists restraint of the right shoulder PsR of the occupant P by the shoulder belt <NUM> in a vehicle head-on collision.

The ceiling-abutment section <NUM> is configured by a substantially elliptical column-shaped second projecting section <NUM> that extends integrally toward the upper side from an upper end portion (upper end face) of the leading end chamber <NUM> at a location corresponding to the auxiliary shoulder-contact section <NUM> when the leading end chamber <NUM> has been inflated and deployed. Namely, as illustrated in <FIG>, the auxiliary shoulder-contact section <NUM> and the second projecting section <NUM> are formed at substantially the same position in the front-rear direction. In other words, as illustrated in <FIG>, the second projecting section <NUM> is formed at a position where at least a part thereof overlaps the auxiliary shoulder-contact section <NUM> in plan view. Thus, the second projecting section <NUM> is disposed at substantially the same position as the first projecting section <NUM> in side view.

As illustrated in <FIG>, a situation in which the left shoulder PsL of the forward-moving occupant P strikes the shoulder-contact section <NUM> and the right shoulder PsR of the occupant P strikes the auxiliary shoulder-contact section <NUM> in a vehicle head-on collision, such that the airbag body <NUM> is pressed forward, and the boundary section <NUM> of the airbag body <NUM> attempts to rotate toward the upper side with the base section 32A of the airbag body <NUM> as a center of rotation in side view can be even more effectively suppressed or prevented by the ceiling-abutment section <NUM> (second projecting section <NUM>).

Namely, the upper end face 46A of the first projecting section <NUM> abuts the ceiling <NUM> and an upper end face 47A of the second projecting section <NUM> abuts the ceiling <NUM>, such that the first projecting section <NUM> (ceiling-abutment section <NUM>) and the second projecting section <NUM> (ceiling-abutment section <NUM>) bear reaction force from the ceiling <NUM>. This suppresses rotation toward the upper side with the base section 32A side of the airbag body <NUM> as a center of rotation, thereby enabling the boundary section <NUM> of the airbag body <NUM> to be more effectively suppressed from riding up toward the upper-front side, and the chest of the occupant P to be more effectively suppressed from pivoting toward the lower side.

Lastly, explanation follows regarding an airbag device <NUM> according to a fourth exemplary embodiment. Note that locations that are equivalent to those in the first exemplary embodiment to the third exemplary embodiment are allocated the same reference numerals, and detailed explanation thereof (including common operation) is omitted as appropriate.

As illustrated in <FIG> and <FIG>, the airbag body <NUM> of the airbag device <NUM> according to the fourth exemplary embodiment only differs from the third exemplary embodiment in the respect that just a single ceiling-abutment section <NUM> that abuts the ceiling <NUM> of the vehicle cabin is integrally formed to an upper end portion of the boundary section <NUM> between the front-rear chamber <NUM> and the leading end chamber <NUM>.

Namely, as illustrated in <FIG>, the ceiling-abutment section <NUM> is configured by just a single substantially elliptical column-shaped third projecting section <NUM> that extends integrally toward the upper side from the upper end portion (upper end face) of the boundary section <NUM> between the front-rear chamber <NUM> and the leading end chamber <NUM> when the front-rear chamber <NUM> and the leading end chamber <NUM> have been inflated and deployed.

As illustrated in <FIG>, a situation in which the left shoulder PsL of the forward-moving occupant P strikes the shoulder-contact section <NUM> the right shoulder PsR of the occupant P strikes the auxiliary shoulder-contact section <NUM> in a vehicle head-on collision, such that the airbag body <NUM> is pressed forward and the boundary section <NUM> of the airbag body <NUM> attempts to rotate toward the upper side with the base section 32A of the airbag body <NUM> as a center of rotation in side view can be even more effectively suppressed or prevented by the ceiling-abutment section <NUM> (third projecting section <NUM>).

Namely, since rotation-inducing moment is greatest on the boundary section <NUM> side of the airbag body <NUM>, the third projecting section <NUM> (ceiling-abutment section <NUM>) effectively bears reaction force from the ceiling <NUM> when an upper end face 49A of the third projecting section <NUM> abuts the ceiling <NUM>. This effectively suppresses rotation toward the upper side with the base section 32A side of the airbag body <NUM> as a center of rotation, thereby enabling the boundary section <NUM> of the airbag body <NUM> to be more effectively suppressed from riding up toward the upper-front side, and the chest of the occupant P to be more effectively suppressed from pivoting toward the lower side.

Although airbag devices <NUM> according to respective exemplary embodiments have been described above with reference to the drawings, the airbag devices <NUM> according to these exemplary embodiments are not limited to those illustrated in the drawings, and various design modifications may be implemented as appropriate within a range not departing from the scope spirit of the present disclosure. For example, the airbag body <NUM> may be stowed in a state folded into a concertina shape. Moreover, the reaction force-withstanding plate <NUM> that supports the inflator <NUM> may be fixed to a headrest support (not illustrated in the drawings) rather than the seatback frame through a bracket (not illustrated in the drawings).

Moreover, the shoulder-contact section <NUM> and the auxiliary shoulder-contact section <NUM> are not limited to sections respectively configured by the rear faces of the extension section 34A and the extension section 36A that extend toward the lower side. For example, the front-rear chamber <NUM> itself and the leading end chamber <NUM> itself may extend toward the lower side, and lower sections of the extended head-restraining face 34B and head-restraining face 36B may be formed with the first shoulder-restraining face <NUM> and the second shoulder-restraining face <NUM> that respectively press the shoulder PsL and shoulder PsR of the occupant P from the front side.

Moreover, the third exemplary embodiment may be configured such that the ceiling-abutment section <NUM> (first projecting section <NUM>) is not formed. Namely, in the case of the airbag body <NUM> of the third exemplary embodiment, a configuration may be applied in which just the ceiling-abutment section <NUM> (second projecting section <NUM>) is formed on the leading end chamber <NUM> side. However, since the front-rear chamber <NUM> is closer to the base section 32A (fixed point 32B) than the leading end chamber <NUM>, the front-rear chamber <NUM> is less liable to rock (its behavior is more stable) than the leading end chamber <NUM>. Thus, the ceiling-abutment section <NUM> (first projecting section <NUM>) is more preferably formed to the front-rear chamber <NUM> than to the leading end chamber <NUM>.

Claim 1:
A vehicle seat (<NUM>) comprising a shoulder belt (<NUM>) and a vehicle airbag device (<NUM>), comprising an airbag body (<NUM>) including:
a front-rear chamber (<NUM>) configured to pass a side of a head (Ph) of an occupant (P) seated in the vehicle seat (<NUM>) and to deploy toward a seat front side as a result of gas being ejected from an inflator (<NUM>) actuated in a case in which a head-on collision of a vehicle is detected or predicted, so as to be disposed at the side of the head (Ph) of the occupant (P);
a leading end chamber (<NUM>) configured to deploy toward a seat width direction inner side from a seat front side end portion of the front-rear chamber (<NUM>) so as to be disposed at the seat front side of the head (Ph) of the occupant (P); and
a shoulder-contact section (<NUM>) configured to contact, from the seat front side, a first shoulder (PsL) of the occupant so as to restrain the first shoulder, the first shoulder being at an opposite side from a second shoulder (PsR) of the occupant (P) across which the shoulder belt (<NUM>) is worn, and
wherein the shoulder-contact section (<NUM>) includes a first shoulder-restraining face (<NUM>) configured to extend toward a seat lower side from a lower end portion of the front-rear chamber (<NUM>).