JP7655843B2 - Knee Air Bag Device - Google Patents

Description

The present invention relates to a knee airbag device that deploys at the feet of the front seat of a vehicle.

It is well known that one or more airbag devices are provided in a vehicle to protect the occupants in the event of a vehicle accident. Airbag devices come in a variety of forms, including a driver airbag device that deploys near the center of the steering wheel to protect the driver, a curtain airbag device that deploys downward inside the window to protect the occupants in the event of a lateral impact or rollover or rollover accident, a side airbag device that deploys on the side of the occupant (the side of the seat) to protect the occupant in the event of a lateral impact, and a knee airbag device that deploys at the feet of the occupant in the front seat. The present invention relates to a knee airbag device.

In the passive safety of a vehicle, it is important that the seat belt restrains the movement of the occupant. Generally, three-point seat belts for the front seats extend diagonally (diagonally) from the top of the B-pillar to the occupant's waist, and the seat belt does not fit over the shoulder on the inside of the vehicle. For this reason, in the event of an oblique collision or offset collision, the occupant's shoulder on the inside of the vehicle (center side, far side) moves forward or rotates outward. Following the rotation of the occupant's upper body, the occupant's torso rotates in a direction facing the outside of the vehicle (near side), and the occupant's outer shoulder, which is restrained by the seat belt, rotates in a direction that causes it to slip out of the seat belt. This reduces the occupant's restraint performance by the seat belt.

The present invention was made in consideration of the above-mentioned circumstances, and aims to provide a knee airbag device that can quickly and reliably restrain the lower limbs of an occupant, thereby preventing a decrease in the ability of the seat belt to restrain the occupant.

In order to achieve the above object, the knee airbag device of the present invention comprises an airbag that inflates and deploys below the instrument panel of a vehicle to restrain the lower legs of an occupant; and an inflator that supplies inflation gas to the airbag. When the inside of the vehicle is defined as a first side and the outside of the vehicle is defined as a second side, the airbag includes a first portion located on the first side and a second portion located on the second side. The first portion of the airbag is configured to protrude toward the occupant more than the second portion.

Alternatively, the knee airbag device according to the present invention includes an airbag that inflates and deploys below the instrument panel of the vehicle to restrain the lower legs of an occupant wearing a seat belt in a vehicle; and an inflator that supplies inflation gas to the airbag. The seat belt extends obliquely from one of the occupant's left or right shoulder to the other lumbar region. When the other side is defined as a first side and the one side is defined as a second side, the airbag includes a first portion located on the first side and a second portion located on the second side. The first portion of the airbag is configured to protrude toward the occupant more than the second portion.

Here, the "inside of the vehicle" can be expressed as the center console side or the far side of the vehicle. Additionally, the "outside of the vehicle" can be expressed as the door side or the near side of the vehicle.

Normally, when a vehicle is involved in an oblique collision or offset collision, the occupant's shoulder on the inside of the vehicle (far side) moves forward or rotates outward, and the occupant's torso rotates in a direction facing the outside of the vehicle (near side). When this happens, the occupant's outside shoulder, which is restrained by the seat belt, rotates in a direction that causes it to slip out of the seat belt. However, by applying the knee airbag device according to the present invention, the first part of the airbag located on the inside of the vehicle protrudes toward the occupant more than the second part located on the outside, so that the occupant's lower leg (knee) on the inside of the vehicle comes into contact with the first part first, and the rotation of the occupant's lower body is suppressed. As a result, the occupant's lower leg can be quickly restrained. In addition, by suppressing the rotation of the occupant's lower body, the rotation of the occupant's upper body is also suppressed, making it possible to maintain the occupant's restraint performance by the seat belt.

The knee airbag device of the present invention can protect occupants sitting in the front seats of a vehicle, such as the driver's seat and passenger seat.

The thickness of the airbag in the vehicle front-rear direction can be set so that the first portion is larger than the second portion.

The thickness of the first and second parts of the airbag can be the same. In this case, it is necessary to consider the shape of the airbag, the deployment direction, the support structure on the first side of the airbag, etc.

The airbag has a first surface facing the occupant and a second surface facing the instrument panel, and first and second baffle plates having different widths in the front-rear direction can be connected between the first and second surfaces inside the airbag.

The baffle plate can be made, for example, from the same fabric as the airbag and connected to the airbag by sewing.

The first baffle plate can be configured to regulate the front-to-rear thickness of the first portion of the airbag, and the second baffle plate can be configured to regulate the front-to-rear thickness of the second portion of the airbag.

The first and second baffle plates are formed with vent holes, and the inflation gas can be configured to flow vertically inside the airbag through the vent holes.

The first and second baffle plates may be provided only in the upper portion of the airbag, not in the lower portion. With respect to a line extending horizontally from the center of the airbag in the vertical direction in the deployed state, the upper side may be referred to as the "upper portion" and the lower side may be referred to as the "lower portion."

Normally, the knees are the most forward part of the body of an occupant seated in a seat, so the occupant can be appropriately restrained by at least designing the shape of the upper part of the airbag. From another perspective, by providing baffle plates only in the upper part of the airbag, the amount (number, area) of baffle plates can be kept to a minimum, which contributes to reducing manufacturing costs.

The inflator can be positioned inside the lower portion of the airbag.

By housing the inflator in the lower part of the airbag where the baffle plate is not located, inflation gas fills the inside of the airbag quickly, which contributes to the quick deployment of the airbag.

The inflator can be disposed on the first side of the airbag.

By placing the inflator on the first side of the airbag, which corresponds to the first portion of the airbag that needs to protrude significantly toward the occupant, it becomes possible to quickly inflate and deploy the first portion, which has a larger capacity.

The first and second parts of the airbag can be structured as separate chambers that are connected to each other.

When the first and second portions are provided as separate chambers, a connecting panel can be provided inside the airbag between the first and second portions to separate the spaces between the two portions.

By providing a connecting panel, the first and second parts inside the airbag can be clearly separated, and the deployed shape of the airbag can be easily changed and controlled between the first and second parts.

The airbag has a rear panel facing the occupant, a front panel facing the instrument panel, a first side panel connected to the edges of the rear panel and the front panel on the first side, and a second side panel connected to the edges of the rear panel and the front panel on the second side, and the width of the first side panel in the front-to-rear direction can be made larger than the width of the second side panel.

By forming the airbag from a front panel, a rear panel, and two side panels, it is possible to maintain a more three-dimensional shape of the deployed airbag. In other words, by adjusting the width of the side airbag, it becomes easier to clearly distinguish the thickness of the first and second parts of the airbag.

The airbag may have a structure in which independent airbag cushions corresponding to the first and second parts are provided and the airbag cushions are connected.

In the present invention, when an occupant sits in a seat in a normal position, the direction that the occupant faces is referred to as "forward" and the opposite direction is referred to as "rearward", and the coordinate axes are referred to as "front-rear direction". When an occupant sits in a seat in a normal position, the right side of the occupant is referred to as the "right direction" and the left side of the occupant is referred to as the "left direction", and the coordinate axes are referred to as "left-right direction". When an occupant sits in a seat in a normal position, the direction of the occupant's head is referred to as "upward" and the direction of the occupant's waist is referred to as "downward", and the coordinate axes are referred to as "up-down direction". Furthermore, in the left-right direction with respect to the occupant, the vehicle center side is referred to as the "inner side" and the door panel side is referred to as the "outer side".

FIG. 1 is a side view showing the knee airbag device according to the present invention in an activated state, and shows the interior of a vehicle compartment as viewed from the side. Fig. 2(A) is a perspective view showing a state in which an occupant is seated in a vehicle seat and fastening a seat belt, and Fig. 2(B) is a top view showing a deployed state of an airbag used in the knee airbag device according to the present invention. FIG. 3 is a plan view showing a panel configuration of an airbag used in the knee airbag device according to the first embodiment of the present invention. Fig. 4(A) is a schematic front view showing the deployed state of the airbag used in the knee airbag device according to the first embodiment of the present invention, and Figs. 4(B) and 4(C) are schematic cross-sectional views taken along the lines AA and BB of Fig. 4(A). FIG. 5 is a plan view showing a panel configuration of an airbag used in a knee airbag device according to a second embodiment of the present invention. Fig. 6(A) is a perspective view showing the deployed state of an airbag used in a knee airbag device according to a second embodiment of the present invention, and Figs. 6(B) and 6(C) are schematic cross-sectional views taken along the lines AA and BB of Fig. 6(A). FIG. 7 is a cross-sectional view showing the deployed state of an airbag used in a knee airbag device according to a third embodiment of the present invention, taken along the line AA in FIG. 6(A).

The following describes in detail the form for carrying out the present invention based on the examples. Fig. 1 is a side view showing the activated state of the knee airbag device 10 according to the present invention, showing the state of the vehicle cabin as viewed from the side. Fig. 2(A) is a perspective view showing the state in which an occupant is seated in the vehicle seat and fastening the seat belt 13. Fig. 2(B) is a top view showing the deployed state of the airbag 10. The knee airbag device according to the present invention can protect occupants seated in the front seats of the vehicle, such as the driver's seat and passenger seat.

As shown in Figures 1 and 2, the knee airbag device of the present invention comprises an airbag 10 that inflates and deploys below the vehicle's instrument panel 11 to restrain the lower legs of an occupant wearing a seat belt 13 inside the vehicle; and an inflator 100 that supplies inflation gas to the airbag 10. The seat belt 13 extends diagonally downward from the top of the B-pillar (not shown) to the occupant's shoulders and waist.

When the inside of the vehicle is defined as the first side and the outside of the vehicle is defined as the second side, the airbag 10 includes a first portion 12 located on the first side and a second portion 14 located on the second side. The first portion 12 is configured to protrude further toward the occupant (rearward) than the second portion 14.

Here, the "inside of the vehicle" can be expressed as the center console side or the far side of the vehicle. The "outside of the vehicle" can be expressed as the door side or the near side of the vehicle. In FIG. 2(A), the above-mentioned "first side" is the right side of the occupant, and the "second side" is the left side.

As shown in FIG. 2B, the thickness of the airbag 10 in the vehicle front-rear direction is greater in the first portion 12 than in the second portion 14. It is also possible to configure the first portion 12 and the second portion 14 of the airbag 10 to have the same thickness, with the first portion protruding toward the occupant.

2A, in the event of a diagonal collision or offset collision, the occupant's shoulder on the inside of the vehicle (far side) generally moves forward or rotates outward as indicated by the arrows, and the occupant's torso follows suit and attempts to rotate in a direction facing the outside of the vehicle (near side).

As shown in FIG. 2(B), in the knee airbag device according to the present invention, the first portion 12 located on the inside of the vehicle of the airbag 10 protrudes toward the occupant more than the second portion 14 located on the outside, so that the occupant's lower leg (knee) LK on the inside of the vehicle comes into contact with the first portion 12 first. As a result, the occupant's movement to slip out of the seat belt 13 can be suppressed, and the occupant's restraint performance by the seat belt 13 can be maintained.

(First embodiment)
Fig. 3 is a plan view showing the panel configuration of airbag 10 used in the knee airbag device according to the first embodiment of the present invention. Fig. 4(A) is a schematic front view showing the deployed state of airbag 10 used in the knee airbag device according to the first embodiment. Figs. 4(B) and (C) are schematic cross-sectional views taken along the lines A-A and B-B of Fig. 4(A).

As shown in FIG. 3, the airbag 10 is composed of one large cloth main panel 17, three large baffle plates 18a, and three small baffle plates 18b. The bag-shaped airbag 10 is formed by folding the main panel 17 from the center and sewing the periphery. Specifically, lines 40a and 40b, 42a and 42b, and 48 and 50 of the main panel 17 are each connected by sewing.

In FIG. 3, line 32a of baffle plate 18a is sewn to line 20a of main panel 17. Also, line 34a of baffle plate 18a is sewn to line 22a of main panel 17. Meanwhile, line 32b of baffle plate 18b is sewn to line 20b of main panel 17. Also, line 34b of baffle plate 18b is sewn to line 22b of main panel 17.

As shown in FIG. 3, the baffle plates 18a, 18b of the airbag 10 are not provided on the lower portion of the airbag 10 (main panel 17), but only on the upper portion. Since the knees are usually the most forward part of the body of an occupant seated in a seat, the effect of the present invention can be achieved by adjusting the shape of the upper portion of the airbag 10. In other words, by adopting such a configuration, the baffle plates 18a, 18b can be kept to the minimum necessary (number, range), which contributes to reducing manufacturing costs.

The baffle plates 18a and 18b can be molded, for example, from the same fabric material as the main panel 17.

As shown in FIG. 4B, the baffle plate 18a regulates the thickness of the first portion 12 of the airbag 10 in the front-rear direction, and the baffle plate 18b regulates the thickness of the second portion 12 of the airbag 10 in the front-rear direction.

As shown in Figures 3 and 4(B), vent holes 60, 62 are formed in the baffle plates 18a, 18b, allowing the inflation gas to flow vertically through the vent holes 60, 62 inside the airbag 10.

As shown in Figures 3, 4(A) and 4(C), the inflator 100 is housed inside the lower part of the airbag 10 (on the first part 12 side). By housing the inflator 100 in the lower part of the airbag 10 where the baffle plates 18a and 18b are not arranged, the interior of the airbag 10 is quickly filled with inflation gas, which contributes to the rapid deployment of the airbag 10. In addition, by arranging the inflator 100 on the first side corresponding to the first part 12 of the airbag 10 that needs to protrude significantly toward the occupant, it becomes possible to quickly inflate and deploy the large-capacity first part 12.

Second Example
Fig. 5 is a plan view showing the panel configuration of airbag 110 used in a knee airbag device according to a second embodiment of the present invention. Fig. 6(A) is a perspective view showing the deployed state of airbag 110 used in a knee airbag device according to the second embodiment. Figs. 6(B) and (C) are schematic cross-sectional views taken along the lines A-A and B-B in Fig. 6(A). Note that repeated explanations of configurations that are the same as or correspond to those of the first embodiment described above will be omitted.

As shown in FIG. 5, in this embodiment, the airbag 110 includes a rear panel 116b facing the occupant, a front panel 116a facing the instrument panel 11, a first side panel 150a connected to the edges of the first side of the rear panel 116b and the front panel 116a, and a second side panel 150b connected to the edges of the second side of the rear panel 116b and the front panel 116a.

The width D1 of the first side panel 150a in the front-rear direction is set to be approximately equal to the width d1 of the baffle plate 18a, and the width D2 of the second side panel 150b is set to be approximately equal to the width d2 of the baffle plate 18b.

In FIG. 5, the outer edge 140a of the front panel 116a is connected to the outer edge 140b of the rear panel 116b by sewing via the side panels 150a and 150b. Also, the line 32a of the baffle plate 18a is sewn to the line 120a of the front panel 116a. Also, the line 34a of the baffle plate 18a is sewn to the line 122a of the rear panel 116b. Meanwhile, the line 32b of the baffle plate 18b is sewn to the line 120b of the front panel 116a, and the line 34b of the baffle plate 18b is sewn to the line 122b of the rear panel 116b.

As shown in FIG. 5, in this embodiment, the airbag 110 is formed by a front panel 116a, a rear panel 116b, and two side panels 150a, 150b. This allows the deployed shape of the airbag 110 to be kept more three-dimensional, as shown in FIG. 6(A). In other words, it becomes easier to clearly distinguish the thickness of the first portion 112 and the second portion 114 of the airbag 110.

(Third Example)
FIG. 7 is a cross-sectional view showing the deployed state of airbag 210 used in a knee airbag device according to a third embodiment of the present invention, and corresponds to the direction AA in FIG. 6(A).

In this embodiment, the first portion 212 and the second portion 214 of the airbag 210 are configured as separate chambers. Inside the airbag 210, a connecting panel 202 is provided between the first portion 212 and the second portion 214 to separate the spaces between the two portions. The connecting panel 202 has a vent hole (not shown) formed therein that communicates with the first portion 212 and the second portion 214.

By providing the connecting panel 202, the first portion 212 and the second portion 214 inside the airbag 210 can be clearly separated, making it easier to deploy the airbag 210 in the desired shape.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments and may be modified within the scope of the technical ideas set forth in the claims. For example, although not shown, each of the chambers configured as separate chambers as shown in FIG. 7 may be prepared as an independent airbag cushion and connected by sewing or the like. In that case, an inflator may be provided for each airbag cushion, and the ignition timing may be adjusted according to the type of collision. Alternatively, a single inflator may be provided, and a gas inlet path connected to each airbag cushion may be prepared, and an active vent may be provided in the gas inlet path, and the active vent may be opened and closed at a predetermined timing according to the type of collision.

Claims (8)

An airbag that inflates and deploys below the vehicle's instrument panel to restrain the lower limbs of an occupant;
an inflator that supplies inflation gas to the airbag;
When an inner side of a vehicle is defined as a first side and an outer side of a vehicle is defined as a second side, the airbag includes a first portion located on the first side and a second portion located on the second side,
In a state where the airbag is inflated and deployed,
The first portion of the airbag protrudes toward an occupant more than the second portion,
the inflator is housed in the first portion of the airbag;
A thickness of the airbag in a vehicle front-rear direction is greater in the first portion than in the second portion,
the airbag has a rear panel facing a passenger side, a front panel facing the instrument panel side, a first side panel connected to edges of the rear panel and the front panel on the first side, and a second side panel connected to edges of the rear panel and the front panel on the second side, the width of the first side panel in the front-rear direction being greater than the width of the second side panel,
Inside the airbag, first and second baffle plates having different widths in a front-rear direction are connected between the rear panel and the front panel, the first baffle plate restricts a thickness of the first portion of the airbag in the front-rear direction, and the second baffle plate restricts a thickness of the second portion of the airbag in the front-rear direction,
a front-rear width of the first side panel on the first side is approximately equal to a width of the first baffle plate, and a front-rear width of the second side panel on the second side is approximately equal to a width of the second baffle plate;
The knee airbag device is configured such that, when the airbag is inflated and deployed, the first portion protrudes toward the occupant more than the second portion, and the occupant's knee on the inside of the vehicle comes into contact with the first portion first, thereby suppressing rotation of the occupant's lower body. The knee airbag device according to claim 1, characterized in that the first and second baffle plates are formed with vent holes, and the inflation gas is configured to be able to flow vertically inside the airbag through the vent holes. The knee airbag device according to claim 1 or 2, characterized in that the first and second baffle plates are not provided in the lower portion of the airbag, but only in the upper portion. The knee airbag device according to claim 3, characterized in that the inflator is disposed inside the lower portion of the airbag. The knee airbag device according to claim 4, characterized in that the inflator is disposed on the first side of the airbag. The knee airbag device according to claim 1 or 2, characterized in that the first and second parts of the airbag are provided as separate chambers and are connected to each other. The knee airbag device according to claim 6, characterized in that a connecting panel is provided between the first and second parts inside the airbag to separate the spaces of both parts. The knee airbag device according to claim 1 or 2, characterized in that the airbag has a structure in which independent airbag cushions corresponding to the first and second parts are provided and the airbag cushions are connected.

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