Patent ID: 12202427

DETAILED DESCRIPTION

Below, exemplary embodiments according to the present disclosure will be explained in detail based on the drawings. It should be noted that, for simplicity of explanation, arrow UP illustrated in the respective drawings indicates an upward direction of a vehicle and a vehicle seat, arrow FR indicates a forward direction of the vehicle and the vehicle seat, arrow LH indicates a leftward direction of the vehicle and the vehicle seat, and arrow RH indicates a rightward direction of the vehicle and the vehicle seat. Accordingly, in the following explanation, in cases in which up-down, front-rear, and left-right directions are described without particular notation to the contrary, these indicate up-down, front-rear, and left-right directions of the vehicle and the vehicle seat. Further, the left-right direction corresponds to the vehicle width direction and the seat width direction.

First Exemplary Embodiment

First, a first exemplary embodiment will be explained. As illustrated inFIG.3A, a vehicle seat12configuring a vehicle occupant restraint structure10according to the first exemplary embodiment is provided at a floor20of a vehicle cabin at a rear side of an instrument panel18. The vehicle seat12includes a seat cushion14at which an occupant P is seated (supporting buttocks and thighs of the occupant P), a seat back16that supports a back of the occupant P, and a headrest17that supports a head Ph of the occupant P.

In a side view viewed in a vehicle width direction (i.e., a seat width direction), the seat cushion14extends in a front-rear direction, and the seat back16is connected to a rear end portion of the seat cushion14so as to be rotatable with the seat width direction as an axial direction, and extends in an up-down direction. The headrest17is provided so as to be able to move up and down at a seat width direction center portion of an upper end portion of the seat back16.

It should be noted that the floor20is made of metal (such as, for example, iron) that is capable of attracting a magnet52, which will be described later. Further, a configuration is provided such that the occupant P is restrained at the vehicle seat12by a seat belt28. A portion of the seat belt28that spans diagonally from a shoulder region Ps to a waist region Pw of the occupant P is a shoulder belt28A, and a portion of the seat belt28that spans leftward and rightward of the waist region Pw of the occupant P is a lap belt28B.

As illustrated inFIG.1A, a cross member22made of metal (such as, for example, iron) that extends in the vehicle width direction is provided at the floor20. The cross member22is formed in a substantially hat-shaped shape in a side view, and a front side flange portion (not illustrated in the drawings) and a rear side flange portion (not illustrated in the drawings) are joined to an upper surface of the floor20by welding or the like. It should be noted that a floor carpet (not illustrated in the drawings) is disposed at the upper surface of the floor20.

Further, front sides of a pair of left and right slide rails36are attached to and supported by an upper surface of the cross member22. The vehicle seat12is configured to be able to move (or slide) in the front-rear direction along the pair of slide rails36. More specifically, as illustrated inFIG.1AandFIG.1B, a cushion pan30made of metal (such as, for example, iron) that configures a bottom portion of the seat cushion14and supports a seat pad (not illustrated in the drawings) is provided at the seat cushion14.

Legs34are provided on both left and right sides of the cushion pan30, and the legs34are respectively supported so as to be slidable at the left and right slide rails36. A slide lever38is disposed at a lower side of a lower surface32A of a front end portion32of the cushion pan30, and has a substantially U-shaped configuration in which a rear side thereof is an open side in a plan view (i.e., a bottom view). The vehicle seat12(or the legs34) is configured such that, by performing an operation to pull up the slide lever38, locking with respect to the slide rails36is released, and the vehicle seat12(or the legs34) becomes slidable in the front-rear direction.

Further, as illustrated inFIG.1A,FIG.1B, andFIG.2A, an airbag40(i.e., an airbag module) that inflates and deploys toward the floor20(i.e., toward the lower side) is provided at the lower surface32A of the front end portion32of the cushion pan30. The airbag40is not provided with a vent hole for exhausting gas, and a length L of the airbag40along the left-right direction is set to a length (for example, 150 mm to 200 mm) sufficient to cover a distance between ischial tuberosities of a large occupant P.

Further, an inflator (not illustrated in the drawings), which is a cylinder-type gas generating device, is provided at a lower surface of the cushion pan30further toward a rear side than the airbag40. The inflator is operable when a front collision of the vehicle has been detected or predicted (hereafter referred to as a “time of a front collision”) so as to be able to instantaneously supply gas to an interior of the airbag40.

It should be noted that an ignition timing of this inflator is preferably the same ignition timing as for an inflator (not illustrated in the drawings) that supplies gas to an airbag provided at a steering wheel (not illustrated in the drawings) or an inflator (not illustrated in the drawings) that actuates a pretensioner (not illustrated in the drawings) of the seat belt28. This is because, since the airbag40does not have a vent hole as described above, an internal pressure can be maintained, and the faster the restraint against the waist region Pw of the occupant P (i.e., suppression of dropping of the waist region Pw) is, the better.

Further, at the interior of the airbag40, plural tethers50(two illustrated in the drawings) having a rectangular cloth shape (i.e., a rectangular shape having the left-right direction as a longitudinal direction thereof) that connect a front wall42and a rear wall44of the airbag40are provided at intervals in the up-down direction. Plural through holes50A are formed at the respective tethers50so as to allow gas supplied from the inflator to flow through the respective through holes50A. A magnet52is provided at an inner surface of a lower wall46, which is an end portion at a deployment direction leading end side of the airbag40.

The magnet52is singly formed in a rectangular flat plate shape having the left-right direction as a longitudinal direction thereof, and is joined to the inner surface of the lower wall46of the airbag40by an adhesive or the like. Accordingly, when the airbag40is inflated and deployed, the magnet52is attracted to the floor20through the lower wall46and the floor carpet. It should be noted that, in order to enable the magnet52to be firmly attracted to the floor20, it is preferable that a portion of the floor carpet (i.e., a portion directly below the magnet52) be formed thinner than the other portions thereof.

Further, as illustrated inFIG.2A, the airbag40is configured so as to be inflated and deployed through the inner side of the slide lever38and so that the rear wall44after inflation and deployment contacts a front wall24of the cross member22, when the vehicle seat12is in a standard position (i.e., a neutral position). Namely, the airbag40after inflation and deployment is configured to be sandwiched between the slide lever38and the front wall24of the cross member22from front and rear directions.

Next, operation of the vehicle occupant restraint structure10according to the first exemplary embodiment configured as described above will be explained.

First, a comparative example will be explained. As illustrated inFIG.6A, the cushion pan (not illustrated in the drawings) of the vehicle seat12is not provided with the airbag40. As illustrated inFIG.6B, when the occupant P, particularly a large occupant, moves toward the front side due to inertial force when a front collision of the vehicle occurs, the front end portion of the seat cushion14deforms (sinks) toward the lower side.

As a result, the waist region Pw of the occupant P drops, a knee region Pk of the occupant P abuts against the instrument panel18and bends, and the lap belt28B, which is a portion of the seat belt28, is relatively displaced toward the upper side and bites into an abdominal region of the occupant P. Namely, restraining force exerted by the seat belt28against the waist region Pw of the occupant P is reduced.

In contrast, in the vehicle occupant restraint structure10according to the first exemplary embodiment, as illustrated inFIG.3A, the airbag40(i.e., the airbag module) that inflates and deploys toward the floor20is provided at the lower surface32A (refer toFIG.1AandFIG.1B) of the front end portion32of the cushion pan30of the vehicle seat12.

Accordingly, when a front collision of the vehicle occurs, the airbag40instantaneously inflates and deploys toward the floor20, and the lower wall46thereof is attracted and fixed to a portion of the floor20due to the magnet52(refer toFIG.2A). Namely, as illustrated inFIG.3B, the airbag40is sandwiched between the cushion pan30and the floor20. Consequently, even if the occupant P moves toward the front side due to inertial force when a front collision of the vehicle occurs, the airbag40inhibits the front end portion of the seat cushion14from deforming (sinking) toward the lower side.

As a result, the waist region Pw of the occupant P is inhibited from dropping, the knee region Pk of the occupant P is inhibited from abutting against the instrument panel18, and the lap belt28B, which is a portion of the seat belt28, is inhibited from relatively displacing toward the upper side. Namely, it is possible to suppress a reduction in the restraining force exerted by the seat belt28against the waist region Pw of the occupant P.

Moreover, the airbag40is configured such that, when the vehicle seat12is in the standard position (i.e., the neutral position), the airbag40is inflated and deployed through the inner side of the slide lever38, and the rear wall44after inflation and deployment contacts the front wall24of the cross member22(refer toFIG.2A). Consequently, swinging of the airbag40at the time of inflation and deployment can be suppressed, and a deployment posture of the airbag40can be stabilized.

Further, the plural tethers50connecting the front wall42and the rear wall44of the airbag40are provided at the interior of the airbag40at intervals in the up-down direction. Accordingly, when a front collision of the vehicle occurs, even if a load (a weight of the occupant P) is applied to the airbag40from the upper side due to the occupant P moving toward the front side due to inertial force, spreading of the airbag40in the front-rear direction can be suppressed. Namely, reduction in height of the airbag40can be effectively suppressed, and deformation (sinking) of the front end portion of the seat cushion14toward the lower side can be effectively suppressed.

Further, since the magnet52is provided at the inner surface of the lower wall46(end portion at the deployment direction leading end side) of the airbag40, the lower wall46of the airbag40after inflation and deployment is attracted and fixed to a portion of the floor20. Accordingly, swinging (particularly movement toward the front side) of the lower wall46of the airbag40after inflation and deployment can be suppressed or prevented, and deformation (sinking) of the front end portion of the seat cushion14toward the lower side can be effectively suppressed.

Further, since the airbag40is used as a suppressing member that suppresses deformation (sinking) of the front end portion of the seat cushion14toward the lower side, the airbag40can be housed compactly (with a small thickness) at normal times, and the front end portion of the seat cushion14can be reliably supported from the lower side until before the occupant P moves toward the front side due to inertial force.

Modified Example

It should be noted that, as illustrated inFIG.2B, instead of providing the magnet52at the inner surface of the lower wall46of the airbag40, a projection26substantially having an inverted L-shape in a side view that extends in the left-right direction, for example, may be provided so as to project at a predetermined position at the floor20on a front side of the cross member22. Namely, a configuration may be provided in which a position of the front wall42at a lower wall46side of the airbag40after inflation and deployment is regulated by the projection26.

Even with such a configuration, since swinging (movement toward the front side) of the lower wall46of the airbag40after inflation and deployment can be suppressed or prevented, deformation (sinking) of the front end portion of the seat cushion14toward the lower side can be effectively suppressed. It should be noted that the shape of the projection26is not limited to the substantial inverted L-shape in a side view that is illustrated in the drawings, and may be any shape that can effectively regulate the position of the front wall42at the lower wall46side of the airbag40after inflation and deployment.

Second Exemplary Embodiment

Next, a second exemplary embodiment will be explained. It should be noted that the same reference numerals are allocated to parts that are equivalent to those in the first exemplary embodiment described above, and that detailed explanation thereof, including common operation, is omitted.

As illustrated inFIG.4A, the vehicle seat12configuring the vehicle occupant restraint structure10according to the second exemplary embodiment is configured so as not to be able to move (slide), i.e., the vehicle seat12is fixed to the floor20. Examples of vehicles in which the vehicle seat12is fixed to the floor20include, for example, Mobility as a Service (MaaS) vehicles and the like.

As illustrated inFIG.4AandFIG.4B, in the vehicle occupant restraint structure10according to the second exemplary embodiment, the airbag40(airbag module), which is inflated and deployed toward the lower surface32A at the front end portion32of the cushion pan30when a front collision of the vehicle occurs, is provided at a portion of the floor20that is positioned directly below the lower surface32A at the front end portion32of the cushion pan30, instead of being provided at the lower surface32A at the front end portion32of the cushion pan30.

Accordingly, the magnet52is provided at an inner surface of an upper wall48, which is the end portion at the deployment direction leading end side of the airbag40. It should be noted that, although not illustrated in the drawings, the inflator is provided at a lower surface side of the floor20. Further, a cut (not illustrated in the drawings) or the like is formed at a portion of the floor carpet that faces the airbag40(airbag module) in the up-down direction, so as to facilitate inflation and deployment of the airbag40by piercing the floor carpet.

As illustrated inFIG.5, according to the vehicle occupant restraint structure10of the second exemplary embodiment configured as described above, when a front collision of the vehicle occurs, the airbag40provided at a portion of the floor20pierces the floor carpet and instantaneously inflates and deploys toward the lower surface32A at the front end portion32of the cushion pan30, and the upper wall48of the airbag40is attracted and fixed to the lower surface32A due to the magnet52.

Namely, in a similar manner as in the above-described first exemplary embodiment, the airbag40is sandwiched between the floor20and the cushion pan30(refer toFIG.3B). Accordingly, even if the occupant P moves toward the front side due to inertial force when a front collision of the vehicle occurs, deformation (sinking) of the front end portion of the seat cushion14toward the lower side is suppressed by the airbag40.

As a result, the waist region Pw of the occupant P is inhibited from dropping, the knee region Pk of the occupant P is inhibited from abutting against the instrument panel18, and the lap belt28B, which is a portion of the seat belt28, is inhibited from relatively displacing toward the upper side. Namely, it is possible to suppress a reduction in the restraining force exerted by the seat belt28against the waist region Pw of the occupant P.

Although explanation has been given above regarding the vehicle occupant restraint structure10according to the present exemplary embodiments based on the drawings, the vehicle occupant restraint structure10according to the present exemplary embodiments is not limited to that which is illustrated in the drawings, and appropriate design modification can be implemented within a range that does not depart from the spirit of the present disclosure. For example, a minute vent hole may be formed at the airbag40so as not to burst.

Further, the shape of the magnet52is not limited to the single rectangular flat plate shape illustrated in the drawings, and, although not illustrated in the drawings, a configuration may be provided in which, for example, the magnet52is configured to have a square shape, and plural magnets52are disposed at predetermined intervals (for example, at equal intervals) in the left-right direction. Furthermore, in the first exemplary embodiment, a configuration may be provided in which an iron plate (not illustrated in the drawings) is provided at the inner surface of the lower wall46of the airbag40, and the magnet52is disposed at a portion of the floor carpet or the floor20(a portion directly below the lower wall46).