JP7626037B2 - Knee airbag device for vehicle - Google Patents

Description

The present invention relates to a knee airbag device for a vehicle.

Patent Document 1 discloses a conventional knee airbag device for a vehicle. This knee airbag device for a vehicle is attached to the instrument panel in front of the passenger seat, and includes an airbag case, a knee airbag, and an airbag door.

An item storage box is attached to the instrument panel so that it can be opened and closed, and an airbag case is disposed below the item storage box. The airbag case has a storage section that opens diagonally downward toward the rear of the vehicle. The storage section contains a knee airbag in a folded state and an inflator that supplies gas to the knee airbag. The opening of the airbag case is closed by an airbag door. The airbag door opens the opening of the airbag case by the inflation pressure of the airbag, allowing the knee airbag to inflate and deploy.

This type of knee airbag device is activated when gas is supplied from an inflator to the knee airbag when a specified impact is applied. The knee airbag inflates from its folded state when gas is supplied. The airbag door receives inflation pressure from the knee airbag and splits open, opening the airbag case. This causes the knee airbag to fly out of the airbag case opening to the rear of the vehicle and inflate and deploy upward and across the vehicle along the item storage box.

However, since the item storage box is attached to the instrument panel so that it can be opened and closed, a gap is inevitably formed between the bottom end of the item storage box and the airbag case or airbag door that are adjacent to that bottom end. If this happens, the knee airbag that protrudes from the opening of the airbag case may get into that gap or collide with the bottom end of the item storage box, which may prevent the knee airbag from inflating and deploying stably.

In this regard, in the above-mentioned conventional knee airbag device for a vehicle, the knee airbag in a folded state housed in an airbag case is covered with a deployment cover member. When an impact is applied, this deployment cover member deploys due to the inflation pressure of the knee airbag to cover the gap between the bottom end of the item storage box and the member adjacent to that bottom end. This prevents the inflated knee airbag from entering this gap or coming into direct contact with the bottom end of the item storage box in this gap. This allows the knee airbag to stably deploy upward.

JP 2017-202769 A

However, the deployment cover member in the above-mentioned conventional vehicle knee airbag device only covers the front and rear faces and the top and bottom faces of the knee airbag in the folded state, and does not cover both side faces of the knee airbag in the vehicle width direction. For this reason, this deployment cover member can only deploy toward the rear and top of the vehicle, and cannot deploy to spread in the vehicle width direction. With a deployment cover member that does not expand in the vehicle width direction, if there is a member adjacent to the airbag case in the vehicle width direction, it is not possible to prevent the knee airbag, which has protruded from the opening of the airbag case and deployed in the vehicle width direction, from coming into contact with the adjacent member in the vehicle width direction.

For this reason, in the above-mentioned conventional vehicle knee airbag device, if there is a nearby component in the vehicle width direction of the airbag case, such as when the device is installed on a lower panel in front of the driver's seat, there is a risk that the stable inflation and deployment of the knee airbag in the vehicle width direction may be hindered.

The present invention was made in consideration of the above-mentioned conventional situation, and the problem to be solved is to provide a knee airbag device for a vehicle that can stably inflate and deploy the knee airbag not only upward but also in the vehicle width direction when the knee airbag is inflated and deployed.

The knee airbag device for a vehicle of the present invention is
an airbag case disposed on an instrument panel and having a housing portion that opens toward the rear of the vehicle;
a knee airbag that is accommodated in the accommodation portion in a predetermined accommodation form and that, when gas is supplied, protrudes from the opening toward the rear of the vehicle and inflates and deploys upward and in the vehicle width direction along the instrument panel;
an airbag door that is displaced between a closed state for closing the opening and an open state for opening the opening by an inflation pressure of the knee airbag to allow the knee airbag to inflate and deploy;
a deployment cover member that is disposed in a predetermined pre-deployment configuration forward of the airbag door in the closed state and that is deployed upward and in the vehicle width direction by the knee airbag that is inflated and deployed to a deployed configuration,
the deployed cover member in the deployed configuration extends upward to a range exceeding a door upper end of the airbag door when in the closed state, and extends in a vehicle width direction to a range exceeding a door side end of the airbag door when in the closed state ,
The deployment cover member in the pre-deployment configuration is in a folded state in which it is folded along a plurality of folding lines,
The plurality of fold lines include a plurality of width direction fold lines extending in a vehicle width direction and a cross direction fold line extending in a direction crossing the width direction fold lines,
The deployed cover member in the pre-deployed configuration is characterized in that it is folded in an accordion-like shape at the plurality of widthwise fold lines and is valley-folded at the intersecting fold lines when viewed from the rear of the vehicle .

The knee airbag device for a vehicle of the present invention is activated when gas is supplied to the knee airbag upon input of a predetermined impact. The knee airbag, housed in a storage section of the airbag case in a predetermined storage form, inflates when gas is supplied. The airbag door receives inflation pressure from the knee airbag and opens the opening of the airbag case. This causes the knee airbag to fly out of the opening of the airbag case to the rear of the vehicle, and to inflate and deploy upward and across the vehicle along the instrument panel.

The deployed cover member, which is located in the pre-deployment state in front of the airbag door in the closed state, deploys upward and in the vehicle width direction as the knee airbag inflates and deploys to the deployed state. At this time, the deployed cover member in the deployed state extends upward to a range that exceeds the upper end of the airbag door in the closed state, and extends in the vehicle width direction to a range that exceeds the door side end in the vehicle width direction of the airbag door in the closed state.

When the knee airbag inflates and deploys in this way, the deployed cover member can be interposed between an upper proximity member that is adjacent to the airbag door above and the inflated and deployed knee airbag if there is such an upper proximity member, or between a side proximity member that is adjacent to the airbag door in the vehicle width direction and the inflated and deployed knee airbag if there is such a side proximity member. This prevents the inflated and deployed knee airbag from directly contacting the upper proximity member or the side proximity member. This allows the knee airbag to stably inflate and deploy upward and in the vehicle width direction.

Therefore, the knee airbag device for a vehicle of the present invention can stably inflate and deploy the knee airbag not only upward but also in the vehicle width direction when the knee airbag is inflated and deployed.

The unfolded cover member in the unfolded form is in a folded state folded at a plurality of fold lines, and the plurality of fold lines may include a plurality of widthwise fold lines extending in the vehicle width direction and a plurality of intersecting fold lines extending in a direction intersecting the widthwise fold lines. The unfolded cover member in the unfolded form is folded in an accordion-like shape at the plurality of widthwise fold lines and is valley-folded at the intersecting fold lines when viewed from the rear of the vehicle.

As a result , the deployed cover member in the pre-deployment form is deployed upward by unfolding the bellows from a state in which it is folded in an accordion shape at the multiple widthwise fold lines. Also, the deployed cover member in the pre-deployment form is deployed outward in the vehicle width direction from the cross-direction fold lines by unfolding the valley-folded cross-direction fold lines. By folding in an accordion shape at the multiple widthwise fold lines, the size of the deployed cover member in the pre-deployment form in the up-down direction can be easily reduced. Also, by making valley folds at the cross-direction fold lines, the size of the deployed cover member in the pre-deployment form in the vehicle width direction can be easily reduced. Therefore, it is easy to ensure a space for arranging the deployed cover member in the pre-deployment form on the vehicle front side of the airbag door in the closed state.

In addition, if the deployment cover member is in a folded pre-deployment configuration, it can be easily fixed by sewing the edge of the deployment cover member in the pre-deployment configuration to the knee airbag. This eliminates the need to provide a separate fixing means for fixing the deployment cover member in the pre-deployment configuration, and simplifies the mounting structure of the deployment cover member.

The knee airbag device for a vehicle of the present invention is capable of stably inflating and deploying the knee airbag not only above the vehicle but also in the vehicle width direction when the knee airbag is inflated and deployed.

FIG. 1 is a schematic diagram illustrating a mounting position of a vehicle knee airbag device according to a first embodiment. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1, showing the configuration of the vehicle knee airbag device of the first embodiment. FIG. 3 is a schematic diagram showing an image of a deployment cover member in a pre-deployment state of the vehicle knee airbag device of the first embodiment. FIG. 4 is a schematic diagram showing an image of the inflated and deployed knee airbag and the deployed cover member in the deployed form in the vehicle knee airbag device of the first embodiment. FIG. 5 is a cross-sectional view illustrating the vehicle knee airbag device of the first embodiment, showing a state in which the knee airbag is inflated and deployed. FIG. 6 is a partially enlarged cross-sectional view showing the vehicle knee airbag device of the first embodiment, in a state in which the knee airbag is inflated and deployed. FIG. 7 is a schematic diagram showing an image of a deployed cover member in a pre-deployment state of the vehicle knee airbag device of the second embodiment. FIG. 8 is a schematic diagram showing an image of a deployed cover member in the deployed form of the vehicle knee airbag device of the second embodiment. FIG. 9 is a schematic diagram showing an image of a deployed cover member in a pre-deployment state of a vehicle knee airbag device according to a third embodiment. FIG. 10 is a schematic diagram showing an image of a deployed cover member in the deployed form of the vehicle knee airbag device of the third embodiment.

Below, we will explain examples 1 to 3 of the present invention with reference to the drawings.

Example 1
The vehicle knee airbag device 10 of the first embodiment is disposed in front of the driver's seat on an instrument panel 12 of a passenger vehicle. In the following description, the vertical direction of the vehicle and the left and right directions in the vehicle width direction are defined by the arrows shown in Fig. 1. The left and right directions in the vehicle width direction are the left and right directions when facing the traveling direction. The front-rear direction and the up-down direction of the vehicle are defined by the arrows shown in Fig. 2. The front-rear direction, the up-down direction, and the left and right directions are mutually orthogonal. In Fig. 3 and subsequent figures, the front-rear direction, the up-down direction, and the left and right directions are defined corresponding to Figs. 1 and 2.

As shown in FIG. 1, a left lower panel 14 and a right lower panel 16 are disposed in the lower portion of the instrument panel 12 in front of the driver's seat. An airbag opening 18 is formed between the lower portion of the left lower panel 14 and the lower portion of the right lower panel 16. A vehicle knee airbag device 10 is disposed in the airbag opening 18. A steering column opening 20 is formed above the airbag opening 18 between the left lower panel 14 and the right lower panel 16. A steering column 24 connected to a steering wheel 22 is disposed in the steering column opening 20.

As shown in FIG. 2, the vehicle knee airbag device 10 includes an airbag case 26, a knee airbag 28, an inflator 30, an airbag door 32, and a deployed cover member 34. In the following description, the deployed cover member 34 in the pre-deployment form will be referred to as the pre-deployment cover member 34a, and the deployed cover member 34 in the deployed form will be referred to as the post-deployment cover member 34b.

The airbag case 26 is made of synthetic resin and is fixed to the airbag door 32 by bolting. The airbag case 26 is in the shape of a roughly rectangular box and has a storage section 36 that opens to the rear of the vehicle. The storage section 36 contains the knee airbag 28, the inflator 30, and the pre-deployment cover member 34a in a stored form. The knee airbag 28 and the inflator 30 are fixed to the airbag case 26 by bolts 38.

The knee airbag 28 inflates and deploys from the opening of the airbag case 26 toward the rear of the vehicle when gas is supplied from the inflator 30. When a predetermined impact is input due to a vehicle collision, the inflator 30 receives an electrical signal from a control unit (not shown) and supplies gas to the knee airbag 28.

The deployed cover member 34 is made of a flexible material, and can be made of, for example, a soft nylon or polyester cloth material. The pre-deployment cover member 34a is disposed in the pre-deployment form on the vehicle front side of the airbag door 32 in the closed state. The pre-deployment cover member 34a is bag-shaped to encase the stored knee airbag 28, and is attached to the airbag case 26 with the knee airbag 28 and the inflator 30 by bolts 38. When stored in the airbag case 26, the pre-deployment cover member 34a has an overlapping portion 341 at the vehicle rear side where the portion that deploys upward and the portion that deploys downward are overlapped, and is sewn at the lower part of this overlapping portion 341. When the knee airbag 38 is folded into a predetermined stored form, it is directly wrapped by the bag-shaped pre-deployment cover member 34a. In FIG. 3, the image shape of the pre-deployment cover member 34a is shown by a two-dot chain line.

As shown in FIG. 3, the pre-deployment cover member 34a has a breakage line 40 that breaks due to the inflation pressure of the knee airbag 28. The breakage line 40 can be formed by a stitched portion or a perforation with a large number of small holes. In FIG. 3, the image shape of the breakage line 40 is shown by a dashed line. The breakage line 40 has a width direction line 40a that extends in the vehicle width direction at the lower part of the pre-deployment cover member 34a, an upper left cross direction line 40b and a lower left cross direction line 40c that extend vertically in a pair from the left end of one width direction end side of the width direction line 40a in a direction perpendicular to the width direction line 40a, and an upper right cross direction line 40d and a lower right cross direction line 40e that extend vertically in a pair from the right end of the other width direction end side of the width direction line 40a in a direction perpendicular to the width direction line 40a.

The upper left crossing direction line 40b is longer than the lower left crossing direction line 40c, and the upper right crossing direction line 40d is longer than the lower right crossing direction line 40e. The upper left crossing direction line 40b and the upper right crossing direction line 40d are the same length, and the lower left crossing direction line 40c and the lower right crossing direction line 40e are the same length. The planned fracture line 40 has a shape symmetrical with respect to the vehicle width center line of the pre-deployment cover member 34a. Therefore, the post-deployment cover member 34b also has a shape symmetrical with respect to the vehicle width center line of the post-deployment cover member 34b (see Figure 4).

If the pre-deployment cover member 34a breaks at the break line 40, it will be deployed upward from the pre-deployment form and will be deployed in both the left and right vehicle width directions to the deployed form. In FIG. 4, the image shape of the post-deployment cover member 34b in the deployed form is shown by a two-dot chain line. This post-deployment cover member 34b extends upward to a range that exceeds the door upper end 32a of the airbag door 32 when it is in the closed state. In addition, the post-deployment cover member 34b extends to a range that exceeds the door left end 32b at one end in the vehicle width direction of the airbag door 32 when it is in the closed state, and extends to a range that exceeds the door right end 32c at the other end in the vehicle width direction of the airbag door 32 when it is in the closed state. Furthermore, the post-deployment cover member 34b extends downward to a range that exceeds the door lower end 32d of the airbag door 32 when it is in the closed state.

The airbag door 32 is made of synthetic resin. As shown in FIG. 2, the airbag door 32 has an engaged portion 44 that can engage with an engaging portion 42 of the left lower panel 14, and also has an engaged portion (not shown) that can engage with an engaging portion (not shown) of the right lower panel 16. The airbag door 32 is fixed to the left lower panel 14 and the right lower panel 16 by engagement between the engaging portion 42 and the engaged portion 44, such as by claw engagement. The airbag door 32 is also fixed to the instrument panel body (not shown), which is made of steel, by bolt fastening.

The airbag door 32 is formed with a tear line 46 as a planned tearing line that will tear due to the inflation pressure of the knee airbag 28. As shown in FIG. 2, the tear line 46 is formed by a groove recessed into the back surface 32e of the airbag door 32 on the vehicle front side. The surface of the airbag door 32 on the vehicle rear side is the design surface 32f.

In FIG. 1, the image shape of the tear line 46 is shown by a dashed line. The tear line 46 has a width direction line 46a that extends in the vehicle width direction at the upper part of the airbag door 32, an upper left cross direction line 46b and a lower left cross direction line 46c that extend vertically from the left end of the width direction line 46a in a pair in a direction perpendicular to the width direction line 46a, and an upper right cross direction line 46d and a lower right cross direction line 46e that extend vertically from the right end of the width direction line 46a in a pair in a direction perpendicular to the width direction line 46a. Note that the shape of the tear line 46 is not limited to this, and can be appropriately set so as to allow the deployment of the knee airbag 28 and the deployment cover member 34. For convenience of explanation, the tear line 46 is omitted from FIG. 3 and FIG. 4.

The airbag door 32 tears open at the tear line 46, deploying upward and downward to open the opening of the airbag case 26. In this way, the airbag door 32 transitions between a closed state in which it closes the opening of the airbag case 26, and an open state in which it tears open at the tear line 46 due to the inflation pressure of the knee airbag 28, opening the opening of the airbag case 26 and allowing the knee airbag 28 to inflate and deploy.

The knee airbag device 10 for a vehicle configured as described above is activated when a predetermined impact is applied and gas is supplied from the inflator 30 to the knee airbag 28. The knee airbag 28, which is stored in the storage section 36 of the airbag case 26 in a predetermined storage form, is inflated by the supply of gas. The airbag door 32, which receives the inflation pressure from the knee airbag 28, tears at the tear line 46, becoming open and exposing the opening of the airbag case 26.

As a result, as shown in Figures 4 to 6, the knee airbag 28 protrudes from the opening of the airbag case 26 to the rear of the vehicle and inflates and deploys upward and in the vehicle width direction along the left lower panel 14 and right lower panel 16 of the instrument panel 12. In Figure 4, the shape of the inflated and deployed knee airbag 28 is shown by a dashed line.

The pre-deployment cover member 34a, which was positioned in the pre-deployment form further forward than the airbag door 32 in the closed state, is deployed upward and in the vehicle width direction by the inflation and deployment of the knee airbag 28 to become the post-deployment cover member 34b in the deployed form. At this time, the post-deployment cover member 34b extends upward to a range that exceeds the door upper end 32a of the airbag door 32 in the closed state, and extends in the vehicle width direction to a range that exceeds the door left end 34b and door right end 34c in the vehicle width direction of the airbag door 32 in the closed state. Furthermore, the post-deployment cover member 34b extends downward to a range that exceeds the door lower end 32d of the airbag door 32 in the closed state.

In the vicinity of the airbag door 32 in front of the driver's seat, there are the left lower panel 14 and the right lower panel 16 as upper and lateral adjacent members. As shown in Figures 4 to 6, when the knee airbag 28 inflates and deploys and the deployed cover member 34 deploys, the deployed cover member 34b can be interposed between the left lower panel 14 and the right lower panel 16 that are adjacent to the airbag door 32 above and the inflated and deployed knee airbag 28, and can also be interposed between the left lower panel 14 and the right lower panel 16 that are adjacent to the airbag door 32 in the vehicle width direction and the inflated and deployed knee airbag 28. Therefore, the inflated and deployed knee airbag 28 does not come into direct contact with the left lower panel 14 and the right lower panel 16.

In addition, even if a gap 50 exists between the airbag door 32 in the closed state and its adjacent member, the instrument panel 12, as shown in FIG. 6, this gap 50 is covered by the post-deployment cover member 34b. Therefore, the inflating knee airbag 28 will not get into the gap 50.

This allows the knee airbag 28 to be stably inflated and deployed upward and in the vehicle width direction.

Therefore, when the knee airbag 28 inflates and deploys, the vehicle knee airbag device 10 can stably inflate and deploy the knee airbag 28 not only upward but also in the vehicle width direction.

In particular, in this vehicle knee airbag device 10, the pre-deployment cover member 34a is bag-shaped to encase the knee airbag 28 in the stored form. The bag-shaped pre-deployment cover member 34a has a planned rupture line 40 that ruptures due to the inflation pressure of the knee airbag 28 to deploy the deployment cover member 34 itself. This planned rupture line 34a has a width direction line 40a extending in the vehicle width direction, an upper left intersecting line 40b and a lower left intersecting line 40c that extend from the left width direction end of the width direction line 40a in a direction perpendicular to the width direction line 40a, and an upper right intersecting line 40d and a lower right intersecting line 40e that extend from the right width direction end of the width direction line 40a in a direction perpendicular to the width direction line 40a.

In this case, the portion of the pre-deployment cover member 34a above the width direction line 40a deploys higher than the pre-deployment cover member 34a. Also, the portion of the pre-deployment cover member 34a that is outboard of the upper left cross direction line 40b and the lower left cross direction line 40c in the vehicle width direction deploys further in the vehicle width direction than the pre-deployment cover member 34a. Also, the portion of the pre-deployment cover member 34a that is outboard of the upper right cross direction line 40d and the lower right cross direction line 40e in the vehicle width direction deploys further in the vehicle width direction than the pre-deployment cover member 34a.

Therefore, by appropriately setting the width direction line 40a and the cross direction lines 40b to 40e of the planned rupture line 40 according to the position, shape, size, etc. of the left lower panel 14 and right lower panel 16 that are adjacent to the airbag door 32 above and in the vehicle width direction, the post-deployment cover member 34b can be reliably interposed between the left lower panel 14, right lower panel 16 and the knee airbag 28.

In this case, the pre-deployment cover member 34a can encase and restrain the knee airbag 28 in the stored configuration, eliminating the need for a separate restraining member to restrain the knee airbag 28, which contributes to reducing the number of parts.

If the inflating knee airbag 28 were to come into direct contact with the left lower panel 14 and the right lower panel 16 or to enter the gap 50, there is a risk that the left lower panel 14 and the right lower panel 16 would be damaged. However, with this vehicle knee airbag device 10, it is possible to prevent such damage to adjacent members.

Furthermore, the gap between the airbag door 32 and its adjacent members can be covered by the cover member 34b after deployment, which increases the tolerance for providing gaps or steps between the airbag door 32 and its adjacent members, improving design freedom.

In addition, because the overlapping portion 341 of the pre-deployment cover member 34a also deploys downward, the post-deployment cover member 34b deploys downward or toward the rear of the vehicle beyond the edge 32g of the airbag door 32 that has split downward, as shown in FIG. 5, preventing the knee airbag 28 from directly contacting the edge 32g of the airbag door 32.

Example 2
As shown in Figures 7 and 8, in the vehicle knee airbag device 10 of the second embodiment, the shape of the planned rupture line 40 in the pre-deployment cover member 34a is changed. The other configurations of this vehicle knee airbag device 10 are the same as those of the vehicle knee airbag device of the first embodiment, and the same configurations are given the same reference numerals and detailed description of the configurations is omitted. For convenience of explanation, the tear line 46 is not shown in Figures 7 and 8, but the airbag door 32 is formed with the same tear line 46 as in the first embodiment.

In FIG. 7, the shape of the planned break line 40 is shown by a dashed line, and the planned break line 40 has a width direction line 40a that extends in the vehicle width direction at the bottom of the pre-deployment cover member 34a, an upper left cross direction line 40b and a lower left cross direction line 40c that extend vertically in a pair from the left end of one width direction end side of the width direction line 40a in a direction intersecting with the width direction line 40a, and an upper right cross direction line 40d and a lower right cross direction line 40e that extend vertically in a pair from the right end of the other width direction end side of the width direction line 40a in a direction intersecting with the width direction line 40a.

The angle at which the upper left crossing direction line 40b intersects with the width direction line 40a is different from the angle at which the lower left crossing direction line 40c intersects with the width direction line 40a. Also, the angle at which the upper right crossing direction line 40d intersects with the width direction line 40a is different from the angle at which the lower right crossing direction line 40e intersects with the width direction line 40a. The upper left crossing direction line 40b is longer than the lower left crossing direction line 40c, and the upper right crossing direction line 40d is longer than the lower right crossing direction line 40e. The upper left crossing direction line 40b and the upper right crossing direction line 40d are the same length, and the lower left crossing direction line 40c and the lower right crossing direction line 40e are the same length. The planned breakage line 40 has a shape symmetrical with respect to the vehicle width center line of the pre-deployment cover member 34a. Therefore, the post-deployment cover member 34b also has a shape symmetrical with respect to the vehicle width center line of the post-deployment cover member 34b (see FIG. 8).

In this case, as in the first embodiment, the portion of the pre-deployment cover member 34a above the width direction line 40a deploys higher than the pre-deployment cover member 34a. Also, the portion of the pre-deployment cover member 34a that is outboard of the upper left intersecting direction line 40b and the lower left intersecting direction line 40c deploys further in the vehicle width direction than the pre-deployment cover member 34a. Also, the portion of the pre-deployment cover member 34a that is outboard of the upper right intersecting direction line 40d and the lower right intersecting direction line 40e deploys further in the vehicle width direction than the pre-deployment cover member 34a.

Therefore, by appropriately setting the width direction line 40a and the cross direction lines 40b to 40e of the planned rupture line 40 according to the position, shape, size, etc. of the left lower panel 14 and right lower panel 16 that are adjacent to the airbag door 32 above and in the vehicle width direction, the post-deployment cover member 34b can be reliably interposed between the left lower panel 14, right lower panel 16 and the knee airbag 28.

Example 3
As shown in Figures 9 and 10, in the vehicle airbag device 10 of the third embodiment, the shape of the deployed cover member 34 is changed. The other configurations of this vehicle knee airbag device 10 are the same as those of the vehicle knee airbag device of the first embodiment, and the same components are given the same reference numerals and detailed description of the configurations is omitted. For convenience of explanation, the tear line 46 is not shown in Figures 9 and 10, but the airbag door 32 is formed with the same tear line 46 as in the first embodiment.

In FIG. 9, the image of the pre-deployment cover member 34a in the pre-deployment form is shown by a two-dot chain line, and the pre-deployment cover member 34a is in a folded state folded at multiple fold lines 48. In FIG. 10, the image of the post-deployment cover member 34b in the unfolded form is shown by a two-dot chain line, and the image of the fold lines 48 is also shown.

The fold lines 48 have multiple widthwise fold lines 48a extending in the vehicle width direction, a left crossing fold line 48b extending perpendicular to the widthwise fold line 48a at the left side of the widthwise fold line 48a, and a right crossing fold line 48c extending perpendicular to the widthwise fold line 48a at the right side of the widthwise fold line 48a. The fold lines 48 are symmetrical with respect to the vehicle width center line of the deployed cover member 34b, and the deployed cover member 34b is substantially semicircular with respect to the vehicle width center line of the deployed cover member 34b (see FIG. 10).

The pre-deployment cover member 34a is folded in an accordion-like shape at multiple widthwise fold lines 48a, and is also valley-folded at left crosswise fold line 48b and right crosswise fold line 48c when viewed from the rear of the vehicle. The edges of the pre-deployment cover member 34a in this folded state are sewn to a bag-shaped restraining member that restrains the knee airbag 28 folded in a specified storage form.

This pre-deployment cover member 34a is folded in an accordion-like shape at multiple widthwise fold lines 48a, and then the accordions are stretched to deploy upward. Also, the pre-deployment cover member 34a is deployed outward in the vehicle width direction from the left intersecting fold line 48b and the right intersecting fold line 48c by stretching the valley folds at the left intersecting fold line 48b and the right intersecting fold line 48c.

By folding in an accordion-like manner at the multiple widthwise fold lines 48a, the size of the pre-deployment cover member 34a in the vertical direction can be easily reduced. In addition, by making valley folds at the left intersecting fold line 48b and the right intersecting fold line 48c, the size of the pre-deployment cover member 34b in the vehicle width direction can be easily reduced. This makes it easier to secure space for positioning the pre-deployment cover member 34a forward of the airbag door 32 in the closed state.

In addition, because the pre-deployment cover member 34a is fixed to the restraining member of the knee airbag 28 by sewing, there is no need to provide a separate fixing means for fixing the pre-deployment cover member 34a, which simplifies the mounting structure of the deployment cover member 34.

Although the present invention has been described above with reference to Examples 1 to 3, it goes without saying that the present invention is not limited to the above Examples 1 to 3, and can be modified as appropriate without departing from the spirit of the present invention.

For example, in the vehicle knee airbag device 10 of Examples 1 and 2, the shape of the planned rupture line 40 in the pre-deployment cover member 34a and the shape of the post-deployment cover member 34b are symmetrical with respect to the vehicle width center line of the post-deployment cover member 34b, but this is not limited thereto, and the shape of the planned rupture line 40 in the pre-deployment cover member 34a and the shape of the post-deployment cover member 34b may be asymmetric with respect to the vehicle width center line of the post-deployment cover member 34b.

In addition, in the vehicle knee airbag device 10 of Examples 1 and 2, the shape of the planned rupture line 40 in the pre-deployment cover member 34a and the shape and size of the post-deployment cover member 34b can be set appropriately depending on the position, shape, size, etc. of the adjacent members adjacent to the airbag door 32.

Similarly, in the vehicle knee airbag device 10 of the third embodiment, the shape of the fold line 48 in the deployed cover member 34 and the shape of the deployed cover member 34b are symmetrical with respect to the center line of the deployed cover member 34b in the vehicle width direction, but this is not limited thereto, and the shape of the fold line 48 in the deployed cover member 34 and the shape of the deployed cover member 34b may be asymmetric with respect to the center line of the deployed cover member 34b in the vehicle width direction.

In addition, in the vehicle knee airbag device 10 of the third embodiment, the shape of the fold line 48 in the deployed cover member 34 and the shape and size of the deployed cover member 34b can be set appropriately depending on the position, shape, size, etc. of the adjacent member adjacent to the airbag door 32.

In the vehicle knee airbag 10 of the third embodiment, the pre-deployment cover member 34a is folded in an accordion-like manner at multiple widthwise fold lines 48a, but this is not limited thereto, and the pre-deployment cover member 34a may be valley-folded at a single widthwise fold line 48a when viewed from the rear of the vehicle. In this case, the pre-deployment cover member 34a is deployed above the widthwise fold line 48a by stretching the valley-folded widthwise fold line 48a.

The vehicle knee airbag 10 in Examples 1 to 3 is disposed on the driver's side of the instrument panel 12, but it may be disposed on the passenger's side instead of the driver's side, or on both the driver's and passenger's seats.

The present invention can be used in vehicles other than passenger cars, such as transport vehicles and industrial vehicles.

REFERENCE SIGNS LIST 10: Vehicle knee airbag device 12: Instrument panel 26: Airbag case 28: Knee airbag 30: Inflator 32: Airbag door 34: Deployment cover member 34a: Pre-deployment cover member 34b: Post-deployment cover member 36: Storage section 40: Predetermined fracture line 40a: Width direction line 40b: Upper left intersecting direction line (intersecting direction line)
40c...lower left cross direction line (cross direction line)
40d...upper right cross direction line (cross direction line)
40e...lower right cross direction line (cross direction line)
48...fold line 48a...width direction fold line 48b...left cross direction fold line (cross direction fold line)
48c...Right crossing fold line (crossing fold line)

Claims (1)

an airbag case disposed on an instrument panel and having a housing portion that opens toward the rear of the vehicle;
a knee airbag that is accommodated in the accommodation portion in a predetermined accommodation form and that, when gas is supplied, protrudes from the opening toward the rear of the vehicle and inflates and deploys upward and in the vehicle width direction along the instrument panel;
an airbag door that is displaced between a closed state for closing the opening and an open state for opening the opening by the inflation pressure of the knee airbag to allow the knee airbag to inflate and deploy;
a deployment cover member that is disposed in a predetermined pre-deployment configuration forward of the airbag door in the closed state and that is deployed upward and in the vehicle width direction by the knee airbag that is inflated and deployed to a deployed configuration,
the deployed cover member in the deployed configuration extends upward to a range exceeding a door upper end of the airbag door when the airbag door is in the closed state, and extends in a vehicle width direction to a range exceeding a door side end of the airbag door when the airbag door is in the closed state ,
The deployment cover member in the pre-deployment configuration is in a folded state in which it is folded along a plurality of folding lines,
The plurality of fold lines include a plurality of width direction fold lines extending in a vehicle width direction and a cross direction fold line extending in a direction crossing the width direction fold lines,
The deployed cover member in the pre-deployment form is folded in an accordion-like shape at the plurality of widthwise fold lines and is valley-folded at the intersecting fold lines when viewed from the rear of the vehicle .

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