JP7215452B2 - Airbag device for knee protection - Google Patents

Description

The present invention relates to a knee-protecting airbag device capable of protecting the knees of an occupant such as a driver or a passenger in a front passenger seat with an airbag that is deployed and inflated by inflating inflation gas.

In a conventional knee-protecting airbag device, an airbag that protects the knees of an occupant has an outer peripheral wall formed by connecting outer peripheral edges of an occupant side wall portion on the occupant side and a vehicle body side wall portion on the vehicle body side, Then, as the inflation completion shape, a mounting portion is provided on the lower side as an upstream portion at the time of inflow of the inflation gas, and has a width dimension in the left-right direction that can be stored in the storage portion, and is attached to the storage portion. On the side, the knee receiving portion is arranged with a width dimension that is widened on both the left and right sides from the mounting portion (see, for example, Patent Document 1). When the airbag is stowed, the occupant side wall portion and the vehicle body side wall portion are overlapped and flatly deployed, and the upper edge side of the knee receiving portion side is rolled to approach the lower edge side of the mounting portion side. The left and right end side portions of the roll-folded roll-folded portion are formed as folded-over portions to be folded over the central portion near the center in the left-right direction of the roll-folded portion, and the folded portions are roll-folded. A folded body is formed by overlapping the central part of the part, and the folded body is stored in the storage part. In such a folded airbag body, when inflation starts, the central portion of the roll-folded portion is inflated and the left and right end side portions are also about to be inflated. Each part expands to the left and right to expand the width dimension in the left and right direction, and expands rearward and upward while unfolding so that the entire roll fold of the roll folding part unwinds. . As a result, such an airbag deploys in a laterally widened state at the initial stage of inflation, and then expands upward while increasing its thickness. Even if the gap between them was narrow, the knee receiving part could be smoothly arranged on the front side of the knee.

Japanese Patent Application Laid-Open No. 2003-170801

However, in the conventional airbag, if the lateral width of the knee receiving portion is wider than the storage portion, the left and right side portions of the roll-folded portion may be displaced from the roll-folded portion. It is necessary to make at least two creases in the central part near the center in the left-right direction of the airbag and store it in the storage part as a folded part. The folded portions (end side portions) on both the left and right sides of the roll-folded portion are expanded in the left-right direction while protruding greatly rearward in the rear region of the central portion of the roll-folded portion as the multiple folds are eliminated. As a result, there is a problem in that the rearward projection amount before being deployed in the left-right direction is increased. By the way, if there is such a problem, for example, if the shin of the passenger is close to the storage part, the tip of the end side part will be in the rear area of the central part of the roll folded part at the beginning of inflation of the airbag. When the airbag expands to the left and right while protruding greatly rearward, it may enter the rear side of the shin of the occupant, and the knee receiving portion of the subsequent airbag may not be arranged smoothly in front of the knee.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a knee-protecting airbag device capable of suppressing the amount of rearward projection of the end side portion of the roll-folded portion of the airbag at the initial stage of inflation. and

In the knee-protecting airbag device according to the present invention, it is folded and stored in a storage portion arranged on the front and lower sides of the knees of a seated occupant, and when the inflation gas flows in, the airbag device moves upward rearward from the storage portion. Equipped with an airbag that deploys and inflates with the occupant and has a knee receiving portion arranged in front of the knee of the occupant,
The airbag is
An outer peripheral wall connecting the outer peripheral edges of the occupant side wall portion on the occupant side and the vehicle body side wall portion on the vehicle body side,
As the inflation completion shape, a mounting portion is provided on the lower side as an upstream portion when the inflation gas flows in, and has a width dimension in the left-right direction that can be stored in the storage portion, and is attached to the storage portion. on the side, the knee receiving portion having a width dimension that is wider on both left and right sides than the mounting portion,
At the time of storage, the occupant side wall portion and the vehicle body side wall portion are overlapped and flattened, and the upper edge side of the knee receiving portion side is rolled so as to approach the lower edge side of the mounting portion side. The left and right end side portions of the folded roll-folded portion are formed as folded-over portions that are folded over the central portion near the center in the left-right direction of the roll-folded portion, and the folded portions are folded into the roll-folded portion. A knee-protecting airbag device having a configuration in which a folded body is formed by overlapping the central part of the body and the folded body is stored in the storage part,
The folded portion on at least one side in the left-right direction of the folded body,
folded over the central portion with at least two creases, and
A first overlapped portion from the first first fold to the second second fold on the central portion side, and a tip side portion that continues to the first overlapped portion and extends to the tip side of the end side portion. and are coupled by a coupling means and disposed,
When the inflating gas flows into the airbag, the first folded portion is unfolded and the first folded portion is removed from the rear region of the central portion. The coupling strength of the coupling means is set so as to release the coupling with.

In the knee-protecting airbag device according to the present invention, when the airbag starts to inflate, the central portion of the roll-folded portion inflates, while the left and right end side portions also try to inflate, so that the folded portion unfolds to the left and right. try to. At that time, in the folded portion in which the joining means is provided and at least two creases are provided and folded over to the central portion, the first folded portion is unfolded to the rear of the central portion. The joining means maintains the folded state until it leaves the region, and the tip portion of the tip side of the end side portion does not move rearwardly away from the first fold portion side of the unfolding fold portion. Then, if the first overlapped portion of the folded portion is unfolded so as to open in the left-right direction so as to separate from the rear region of the central portion of the roll folded portion, the coupling means will connect the first overlapped portion and the tip side portion. Since the coupling is released, the folding of the second fold is canceled, and the folded portion itself unfolds the tip side of the tip side portion in the left-right direction. Therefore, the folded portion folded in the central portion with at least two creases is uncoupled by the coupling means after the first folded portion is unfolded in the left-right direction along with the unfolding of the first fold. Along with this, the second fold is eliminated, the tip side portion is expanded in the left and right direction, and then the first overlapping portion and the tip side portion that are expanded in the left and right direction together with the central portion of the roll folded portion. The end side portion provided with the cancels the folding of the roll folding, and the knee receiving portion is arranged on the front side of the knee. That is, by the time the connecting means releases the connection, the folded portion is restrained from protruding rearward and expands widely in the left-right direction. At the initial stage of inflation of the airbag, the tip of the end side portion of the folded portion does not protrude greatly rearward in the rear region of the central portion of the roll folded portion, and extends left and right from the rear region of the central portion of the folded roll portion. Since it is possible to unfold the roll-folding in a state in which it is released and spread out to the left and right, the knee receiving portion, which has been arranged in the central portion of the roll-folding portion and the folding portion, can be smoothly It can be placed on the front side of the knee.

Therefore, in the knee-protecting airbag device according to the present invention, the coupling means can suppress the rearward projection amount of the end side portions of the roll-folded portion of the airbag at the initial stage of inflation.

In the knee-protecting airbag device according to the present invention, one of the left and right folding parts of the folded body is provided with at least two folds and folded over to the central part,
The coupling means may be provided and arranged.

That is, the folded body may be formed by providing a coupling means only on one of the left and right folded parts of the folded body, which needs to be restrained from protruding rearward at the initial stage of expansion. good.

In this case, when the airbag is completely inflated, the mounting center, which is the center of the mounting portion in the left-right direction, is positioned on one side in the left-right direction from a center line in the front-rear direction that passes through the center of the knee support portion in the left-right direction. It is configured to be arranged by shifting to
The end side portions on both left and right sides of the roll folded portion are folded toward the attachment center side in the central portion of the roll folded portion to form the folded portion,
The folded portion of the folded body on the side where the connecting means is provided may be a portion on the side of the center line deviating from the mounting center.

In such a configuration, when the airbag at the time of completion of inflation is shifted in the left-right direction from the center line passing through the center of the knee support portion in the left-right direction, the left and right end sides of the roll folded portion In this case, since the side that is shifted away from the mounting center of the mounting portion as one side has a longer length dimension than the other side, it is coupled to the folded portion of the end side portion of the long dimension on that one side. By disposing means, the folded portion can be expanded in the left-right direction accurately while suppressing the amount of rearward protrusion, and then expanded and expanded in such a manner as to unroll the roll. In the knee-protecting airbag device having such a configuration, even if the knee receiving portion of the airbag is arranged in front of the center of the right and left knees of the occupant in the left-right direction, can not be arranged in front of the center of the occupant's left and right knees in the left-right direction.

Of course, the connecting means may be provided not only on one of the left and right folded parts of the folded body, but also on both left and right folded parts.

Further, in the knee-protecting airbag device according to the present invention, the connecting means is formed, for example, by wrapping the entire periphery of the folded portion along the front-rear direction with a breakable tape material, The tape material may constitute the connecting means by setting the strength of the tape material to be broken when the first overlapped portion and the distal end portion are disconnected.

Alternatively, the connecting means is formed by attaching a breakable tape material from the front surface side of the central portion on the outer peripheral side of the first fold to the rear surface side of the folded portion, and the tape material is formed , The connecting means may be configured to have a strength set to be broken when the first overlapped portion and the distal end portion are disconnected.

Further, as the connecting means, a flexible sheet material having both ends sewn to the front surface side of the central portion on the outer peripheral side of the first fold and the rear surface side of the folded portion is used. wherein the sheet material is positioned near an intermediate portion between the stitched portions to the front surface side of the central portion and the rear surface side of the folded portion when the connection between the first overlapped portion and the tip side portion is released. , and a portion to be broken to be broken may be arranged to constitute the connecting means.

Furthermore, the coupling means may include a shaft penetrating the first overlapped portion and the tip side portion, and a shaft portion disposed at both ends of the shaft portion to connect the first overlapped portion and the tip side portion. and a locking head that is locked to the surface side of the locking member, and the locking member is formed from the locking head when the coupling between the first overlapped portion and the tip side portion is released. The coupling means may be configured with a strength that separates the protrusions from each other.

Further, the connecting means is formed of a cover that fits the folded portion so as to wrap the folded portion from the vicinity of the second fold, and the cover connects the first overlapped portion and the tip side portion. The coupling means may be configured to have a fitting strength that separates from the folded portion when the coupling is released.

It should be noted that the tape material, sheet material, engaging member, or cover described above may be composed of a plurality of the same ones or a combination of different ones to constitute the coupling means.

In this case, when the connecting means is configured by combining different parts, it is necessary to increase the variation of the control of the deployment direction of the airbag at the time of releasing the connection between the first overlapped portion and the tip side portion, or after that. can be done.

Also, when using the same tape material, for example, when using a plurality of tape materials, if they are arranged at a distance from each other, one tape material can be used to fold the folded part without gaps. Compared to the case of wrapping, the amount of tape material used can be reduced, and the weight can be reduced.

Further, in the knee-protecting airbag device according to the present invention, the folded portion of the folded body is folded back at the first overlapping portion and the second folding portion to overlap the first overlapping portion. and a second overlapping portion as a tip side portion.

Further, in the knee-protecting airbag device according to the present invention, the tip side portion extending to the tip side of the end side portion connected to the first overlapping portion in the folded portion of the folded body is the second tip side portion. A third fold is provided at the tip of the fold, and a second overlapped portion extending from the second fold to the third fold, and a third overlapped portion extending from the third fold are provided. As a configuration,
The third overlapping portion may be arranged between the first overlapping portion and the second overlapping portion.

Alternatively, in the knee-protecting airbag device according to the present invention, the distal end side portion extending to the distal end side of the end side portion continuing to the first overlapping portion of the folded portion of the folded body may be the second folding portion. A third fold is provided at the tip of the fold, and a second overlapped portion extending from the second fold to the third fold, and a third overlapped portion extending from the third fold are provided. As a configuration,
The third overlapped portion may be overlapped on a side of the second overlapped portion, which is overlapped on the first overlapped portion, away from the first overlapped portion.

1 is a schematic vertical cross-sectional view of a knee-protecting airbag device according to an embodiment of the present invention mounted on a vehicle; FIG. 1 is a schematic enlarged vertical cross-sectional view of a knee-protecting airbag device according to an embodiment; FIG. 1 is a schematic front view of a knee-protecting airbag device according to an embodiment mounted in a vehicle; FIG. 1 is a schematic cross-sectional view of a knee-protecting airbag device according to an embodiment mounted on a vehicle; FIG. The bottom view, the top view, and the schematic longitudinal cross-sectional view of the airbag used for the airbag apparatus for knee protection of embodiment are shown, respectively. It is a figure which shows the structural material of the airbag of embodiment. It is a figure explaining the process of folding the airbag of embodiment and forming a folding completion body. It is a figure explaining the operating state of the knee protection airbag apparatus of embodiment in order. It is a figure explaining the operating state of the knee protection airbag apparatus of a comparative example. It is a figure which shows the modification of the coupling means used for the folding complete body of the airbag of embodiment. It is a figure which shows the other modified example of the connection means used for the folding complete body of the airbag of embodiment. FIG. 10 is a view showing still another modification of the coupling means used in the folded airbag body of the embodiment; FIG. 10 is a view showing still another modification of the coupling means used in the folded airbag body of the embodiment; It is a figure which shows the modification of the folding part of the folding completion body of the airbag of embodiment. It is a figure which shows the other modification of the folding part of the folding completion body of the airbag of embodiment. FIG. 10 is a view showing still another modification of the coupling means used in the folded airbag body of the embodiment; FIG. 10 is a view showing still another modification of the coupling means used in the folded airbag body of the embodiment; FIG. 10 is a view showing still another modification of the coupling means used in the folded airbag body of the embodiment; FIG. 10 is a view showing still another modification of the coupling means used in the folded airbag body of the embodiment; FIG. 10 is a view showing still another modification of the coupling means used in the folded airbag body of the embodiment;

An embodiment of the present invention will now be described with reference to the drawings. As shown in FIGS. ) below the steering column 2 on the vehicle front side of the driver M, that is, on the front lower side of the knee K. As shown in FIG.

As shown in FIG. 1, the steering column 2 includes a main shaft 3 that is covered by a column cover 5 and connected to the steering wheel 1, and a column tube 4 that surrounds the main shaft 3. Between the main shaft 3 and the column tube 4, a tilt mechanism (not shown) capable of adjusting the angle of the ring surface of the steering wheel 1 and a telescopic mechanism (not shown) capable of moving the steering wheel 1 in the axial direction of the shaft 3 and stopping it are provided. Mechanisms and the like are provided.

The column cover 5 is made of a synthetic resin and has a substantially square tubular shape, and is arranged along the axial direction of the steering column 2 so as to cover the steering column 2 below the steering wheel 1 so as to be inclined rearwardly upward. there is The column cover 5 is surrounded by an instrument panel (instrument panel) 6 comprising an upper panel 6a and a lower panel 6b in front of the driver M. , and has a substantially rectangular shape, and is formed in a curved surface that rises rearward in the longitudinal direction of the vehicle.

The knee-protecting airbag device KA includes a folded airbag 30, an inflator 24 that supplies inflation gas to the airbag 30, an airbag cover 18 that covers the folded airbag 30, and the folded airbag 30. and a case 10 for housing an inflator 24, and mounted under a column cover 5 on the vehicle body side, surrounded by a lower panel 6b of an instrument panel 6. - 特許庁

The case 10 is a housing portion for the airbag 30, and is made of sheet metal and has a bottom wall portion 11 disposed on the front side and a peripheral wall portion 14 extending rearward from the peripheral edge of the bottom wall portion 11 in a substantially square tubular shape. The rear end side serves as a projection opening 10a for projecting the airbag 30 when inflated. Mounting holes 11a through which bolts 26a for mounting the inflator 24 and the airbag 30 are passed through are provided side by side in the bottom wall portion 11, and mounting pieces 12 extending in the left and right direction are provided. Each attachment piece 12 has a through hole 12a through which a bolt 9 passes, and the airbag device KA is attached to the attachment bracket 8 on the body side using the bolt 9. As shown in FIG. Each bolt 9 passes through a through hole 12 a and is fastened to a nut 8 a fixed to the mounting bracket 8 . Further, the bottom wall portion 11 is provided with a holding projection 11b for firmly holding a main body 25 of the inflator 24, which will be described later, on the retainer 26. The holding projection 11b protrudes rearward.

The peripheral wall portion 14 includes an upper wall portion 14a, a lower wall portion 14b, a right wall portion 14c, and a left wall portion 14d arranged vertically and horizontally. , is formed with a plurality of hooks 15 that are inserted into locking holes 22a of the mounting wall portion 22 of the airbag cover 18 to lock the mounting wall portion 22 at the front end (rear end). A connector 28 to which a lead wire 29 for inputting an operation signal to the inflator 24 is connected can be connected to the base portion 25b side of the main body 25 of the inflator 24 on the right wall portion 14c. , the insertion hole 16 is opened.

The airbag cover 18 is formed of a thermoplastic elastomer such as polyolefin, and as shown in FIGS. and a mounting wall portion 22 having a substantially square tubular shape.

The design surface portion 19 is provided with door portions 20 (U, D) that are pushed by the airbag 30 when inflated and open up and down. Each of the door portions 20U and 20D is arranged so as to block the rear side of the projecting opening 10a of the case 10, and surrounds the substantially H-shaped thin portion to be broken 21 when viewed from the rear side of the design surface portion 19. When the airbag 30 is inflated, the portions to be broken 21 are broken, respectively, and the hinge portions 20a, 20a, which are integral hinges at the upper and lower edges, are opened as the center of rotation.

A plurality of locking holes 22a for locking the hooks 15 of the case 10 are formed in the portions of the mounting wall portion 22 facing each other in the vertical direction.

As shown in FIGS. 1, 2 and 4, the inflator 24 includes a substantially cylindrical main body 25 and a substantially cylindrical retainer 26 that holds the main body 25 . The main body 25 has a gas discharge portion 25a for discharging inflation gas at the tip (left end), and a connector 28 for inputting an operation signal is connected to the base portion 25b. The retainer 26 includes bolts 26a for attaching the inflator 24 to the bottom wall portion 11 of the case 10, and has through holes 26b through which the holding protrusions 11b of the case 10 pass. The inflator 24 is housed in the case 10 with the main body 25 inserted into the retainer 26, and the bolts 26a protrude from the case 10 to the outside of the case 10 through the mounting holes 11a. When the nut 27 is fastened to the bolt 26a, the holding projection 11b of the case 10 presses the main body 25 through the through hole 26b of the retainer 26, and presses the main body 25 against the inner peripheral surface of the retainer 26. By fastening the retainer 27, the retainer 26 of the inflator 24 can be attached to the case 10, and the retainer 26 can hold the main body 25 firmly. It will be attached and fixed to the case 10 at this time. Of course, at the time of this fixing, the later-described mounting portion 31 of the airbag 30 is also sandwiched between the inflator 24 and the bottom wall portion 11 of the case 10 and is firmly mounted and fixed to the case 10 .

The inflator 24 is actuated by inputting an actuation signal from a control device (not shown) mounted on the steering wheel 1 for actuating the airbag device at the same time as the airbag device for the steering wheel.

The airbag 30 is made of a flexible woven fabric such as polyester or polyamide, and as shown in FIGS. 35 and an outer peripheral wall 34 that connects the outer peripheral edges to each other. The airbag 30 has a substantially rectangular plate-like shape whose inflation completion shape is similar to the shape of the home base. A mounting portion 31 attached to the case 10 is provided as a width dimension in the direction, and a knee receiving portion 32 having a width dimension in which the left and right sides of the mounting portion 31 are widened is provided on the upper side.

The mounting portion 31 includes two mounting holes 31a arranged side by side in the lateral direction of the vehicle body side wall portion 35, through which two bolts 26a of the inflator 24 are inserted. 24 is provided with an insertion hole 31b through which the root portion 25b of the main body 25 can be inserted.

Further, inside the airbag 30, the separation distance between the vehicle body side wall portion 35 and the occupant side wall portion 36 is regulated when the airbag 30 is completely inflated, and the airbag 30 is inflated into a plate shape having a substantially constant thickness. The tethers 38 (U, M, D) connecting the vehicle body side wall portion 35 and the occupant side wall portion 36 are arranged in three upper and lower stages. Each tether 38 is arranged along the left-right direction, and gas flow holes 39 for upward flow of the inflation gas G are opened at two locations separated from each other in the left-right direction.

In addition, the airbag 30 of the embodiment is centered on the center line BL in the front-rear direction that passes through the left-right center of the knee receiving portion 32 on the side of the upper portion 30a, except for the vicinity of the mounting portion 31 that narrows downward on the lower end side. It has a substantially symmetrical shape. However, in the airbag 30, the two mounting holes 31a of the mounting portion 31 are arranged so as to be shifted to one side in the horizontal direction, that is, to the right side in the case of the embodiment, with respect to the center line BL. That is, if the center between the two mounting holes 31a, 31a of the mounting portion 31 of the airbag 30 is defined as the mounting center MC, the center line ML in the longitudinal direction passing through the mounting center MC is the knee support portion in the case of the embodiment. 32 is shifted to the right side of the center line BL passing through the center of 32 (see FIG. 5). Such deviation of the center line ML from the center line BL is the center line passing through the center of the knee receiving portion 32 corresponding to the center (knee center) KC between the left and right knees KL and KR of the driver (passenger) M. Even if the line BL is arranged, the arrangement position of the mounting portion 31 of the airbag 30 may be shifted left and right with respect to the center line BL depending on the arrangement of various devices and members around the knee-protecting airbag device KA in the vehicle. This occurs when there is no choice but to displace to one side (right side in the embodiment) (see FIG. 3).

The left and right end portions 55 and 56 of the roll-folded portion 53 where the airbag 30 is roll-folded are folded toward the mounting center MC side of the center portion 54 near the center in the left-right direction of the roll-folded portion 53 . It will overlap (see FIG. 7).

As shown in FIGS. 5 and 6, the components of the airbag 30 include an upper end side base cloth 41 arranged in an inverted U shape on the side of the upper end 34a of the outer peripheral wall 34, and an upper end side cloth 41 bent in an inverted U shape. A vehicle body-side base cloth 42 and an occupant-side base cloth 43 extending downward from both ends (lower ends) of the base cloth 41 and arranged to face each other form respective tethers 38 (U, M, D). and tether base cloth 44 (U, M, D). When manufacturing the airbag 30, the upper end side base cloth 41 is folded in two, and the upper end sides of the vehicle body side base cloth 42 and the occupant side base cloth 43 are sewn to both end sides, respectively, and then folded in two. While sewing the front and rear ends of each of the tether base cloths 44U, 44M, and 44D to the portion of the upper end side base cloth 41 facing each other and the portions of the vehicle body side base cloth 42 and the occupant side base cloth 43 facing each other, the occupant The airbag 30 can be manufactured by stitching the overlapped portions of the side wall portion 36 and the vehicle body side wall portion 35 to form the outer peripheral edges.

When folding the manufactured airbag 30 and arranging the tape material 72 as the connecting means to form the folded body 70 that can be stored in the case 10 as the storage portion, the airbag 30 is firstly folded. Fold. 7A and 7B, the occupant side wall portion 36 and the vehicle body side wall portion 35 are overlapped to form an initial deployment body 50 that is flatly deployed. A roll-folded body 52 is formed by roll-folding on the vehicle body side wall portion 35 side so that the upper edge 50a side approaches the lower edge 50b side of the mounting portion 31 side. After that, as shown in FIGS. 7B and 7C, the left and right end portions 55 and 56 of the roll-folded portion 53 of the roll-folded body 52 are pushed toward the center of the roll-folded portion 53 in the left-right direction. Folded portions 59 (L, R) are formed on the occupant side wall portion 36 side with respect to the central portion 54 of the roll folded portion 53, and the folded portions 59L, 59R are formed on the rear surface 54b of the central portion 54 of the roll folded portion 53. overlaid on

In the embodiment, the folds 59L, 59R are each folded into the central portion 54 with two folds 59a, 59b. That is, each of the folded portions 59L and 59R is divided into the first folded portion 60 from the first first fold 59a to the second second fold 59b on the central portion 54 side, and the first folded portion 60. and a distal end side portion 61 extending to the distal end side of the end side portions 55 and 56 in a row. In the case of the embodiment, the distal end portion 61 is folded to the rear surface side of the first overlapping portion 60 as the second overlapping portion 62 . Further, in the folded portions 59L and 59R, the center line ML of the mounting portion 31 is shifted to the right with respect to the center line BL of the airbag 30, and the left folded portion 59L is located more than the right folded portion 59R. , the length in the left-right direction is increased (the length in the left-right direction LL of the left folded portion 59L>the length in the left-right direction LR of the right folded portion 59R).

A tape material 72 as a connecting means wraps the entire circumference of the front-rear direction outer periphery of the first overlapped portion 60 near the first fold 59a of the left folded portion 59L on the long dimension side and the tip side portion 61. It is affixed so that The tape material 72 is formed by applying an adhesive to a woven fabric made of yarn such as polyester or polyamide, and is breakable. In particular, the breaking strength of the tape material 72, in other words, the bonding strength of the tape material 72 wrapped so as to bond the first overlapping portion 60 and the tip end portion 61, is 8A to 8C, the first fold 59a is unfolded, and the first folded portion 60 of the folded portion 59L is removed from the rear region BA of the central portion 54 of the roll folded portion 53. The breaking strength of the tape material 72 is set so as to release the connection between the first overlapped portion 60 and the distal portion 61 . In more detail, the breaking strength of the tape material 72 will be described. flows, the center portion 54 swells, further flows into the first folded portion 60 side of the folded portion 59L so as to unfold the first fold 59a, and furthermore, the second fold 59b is folded. It flows into the tip side portion 61 (second overlapping portion 62) so as to eliminate the , but is set so as to secure a breaking strength that can inhibit the unfolding of the second fold 59b to some extent. The first overlapped portion 60 expands, the distal end portion 61 expands, and the tip portion 61 rotates about the second fold 59b so that the distal end portion 61 is separated from the first overlapped portion 60, so as not to break. The breaking strength of the tape material 72, that is, the bonding strength of the tape material 72 between the first overlapping portion 60 and the distal end side portion 61 is set.

Then, the folded body 70 can be formed by winding the tape material 72 and forming the integrated swinging portion 65 by connecting the first overlapped portion 60 and the tip portion 61 of the folded portion 59L. After that, the folded body 70 is wrapped with a breakable wrapping film 47 (see FIG. 2) for preventing collapse of the folded body.

When the airbag 30 is folded, the retainer 26 of the inflator 24 is housed inside the airbag 30 by projecting the bolt 26a from the mounting hole 31a of the mounting portion 31 (not shown). When wrapping the folded body 70 with the wrapping film 47, the portion of the wrapping film 47 in the area of the insertion hole 31b of the mounting portion 31 is broken, and the bolt 26a is also protruded from the wrapping film 47. back.

After that, the body 25 of the inflator 24 is inserted into the retainer 26 through the insertion hole 31b of the airbag 30, the folded body 70 containing the inflator 24 is housed in the case 10, and the bolts 26a, 26a are tightened. The inflator 24 and the airbag 30 are attached and fixed to the case 10 by protruding from the attachment holes 11a of the bottom wall portion 11 and fastening nuts 27 to the respective bolts 26a. Then, while disposing the design surface portion 19 of the airbag cover 18 so as to close the projecting opening 10a of the case 10, the mounting wall portion 22 is fitted around the peripheral wall portion 14 of the case 10, and the hook 15 of the case 10 is mounted. The airbag device KA can be assembled by inserting it into the locking hole 22a of the wall portion 22. As shown in FIG.

The airbag device KA assembled in this manner is assembled by applying the mounting piece 12 of the case 10 to the mounting bracket 8 of the vehicle before the instrument panel 6 is assembled, and inserting the bolts 9 through the through holes 12a and the nuts 8a. , the airbag device KA can be assembled to the vehicle, a connector 28 having a lead wire 29 capable of inputting an operation signal is assembled to the main body 25 of the inflator 24, and the instrument panel 6 is assembled to the vehicle. Then, the knee-protecting airbag device KA can be mounted on the vehicle.

After the airbag device KA is mounted on the vehicle, if the vehicle experiences a frontal collision and the inflator 24 is activated, the inflation gas G is discharged from the gas discharge portion 25a, and the airbag 30 starts to inflate. A folded portion 59 (L, R) consisting of a central portion 54 and end side portions 55, 56 of the roll folded portion 53 expands to push open the door portions 20U, 20D of the airbag cover 18, thereby projecting the case 10. The folded portions 59 (L, R) protrude rearward from the opening 10a and are unfolded so as to unfold the folds 59a and 59b. To solve this problem, the knee receiving portion 32 is arranged in front of the knees K of the driver M by extending rearward and upward from the case 10 as a storage portion of the airbag 30 .

At this time, in the knee-protecting airbag device KA of the embodiment, when the airbag 30 starts to inflate, the center portion 54 of the roll folded portion 53 is inflated, and the left and right end portions 55 and 56 are also about to inflate. , the folded portions 59 (L, R) tend to unfold to the left and right. At that time, as shown in FIGS. 8A and 8B, a tape material 72 as a connecting means is provided, and at least two creases 59a and 59b are provided, and the folded over center portion 54 is elongated in the left-right direction. In the folded portion 59L, the folded state is maintained by the tape material 72 as a connecting means until the first folded portion 59a is unfolded and the first folded portion 60 is removed from the rear area BA of the central portion 54. , the distal end portion 61 on the distal end side of the end side portion 55 does not move rearward away from the unfolded folded portion 59L on the first overlapping portion 60 side. Then, if the first folded portion 60 of the folded portion 59L is unfolded to open leftward in the horizontal direction so as to deviate from the rear area BA of the center portion 54 of the roll folded portion 53, B, FIG. As shown in C, the tape material 72 as a connecting means releases the connection between the first overlapping portion 60 and the tip end side portion 61, so that the second fold 59b is unfolded and the folded portion 59L itself is formed. However, the tip 62a side of the tip side portion 61 is expanded leftward in the left-right direction. Therefore, the folded portion 59L, which is provided with at least two folds 59a and 59b and is folded over at the central portion 54, expands in the left-right direction of the first folded portion 60 as the first fold 59a is unfolded. Later, as the tape material 72 as the binding means is released, the second crease 59b is removed, the tip end portion 61 is expanded leftward in the left-right direction, and then the center of the folded roll portion 53 is opened. Along with the portion 54, the end side portion 55 comprising the first overlapped portion 60 and the tip end side portion 61 expanded in the left-right direction eliminates the folding of the roll folding, as shown by the two-dot chain line in FIG. , the knee receiving portion 32 is disposed on the front side of the knee K. That is, by the time the tape material 72 as the connecting means releases the connection, the folded portion 59L is restrained from protruding rearward and expands widely in the left-right direction. Even if S(L, R) is close to the case 10 as the housing portion, the tip 62a of the end side portion 55 of the folded portion 59L is positioned at the central portion of the folded roll portion 53 when the airbag 30 is initially inflated. The folding of the roll folding can be canceled in a state in which the rear area BA of the roll folding part 53 does not largely protrude rearward and the rear area BA of the central part 54 of the roll folding part 53 is laterally unfolded to the left and right. Therefore, the knee receiving portion 32, which has been arranged in the region of the central portion 54 of the roll folding portion 53 and the folded portions 59 (L, R), can be smoothly arranged on the front side of the knee K. .

If the tape material 72 as the connecting means is not provided, as shown in FIGS. 9A and 9B, at the initial stage of inflation of the airbag 30, the tip 62a of the end side portion 55 of the folded portion 59L is The rear region BA of the central portion 54 of the roll folding portion 53 protrudes greatly rearward, and behaves as if it enters the back side of the left shin SL from between the approaching shins SL and SR. The receiving portion 32 cannot be arranged on the front side of the knee K.

In addition, the right folded portion 59R has a short lateral length LR, so that even if it is not wrapped with the tape material 72, the tip 62a can enter the back side of the approaching shin SR. It can be deployed and inflated without causing it.

Therefore, in the knee-protecting airbag device KA of the embodiment, the tape material 72 as the connecting means suppresses the rearward protrusion amount of the end side portion 55 of the roll-folded portion 53 of the airbag 30 at the initial stage of inflation. be able to.

As a result, in the embodiment, even if the shins S (L, R) of the driver (passenger) M are close to the case 10 as the storage portion, the folded portions 59L and 59R of the roll folded portion 53 are smoothly folded. Then, the front side of the shin S (L, R) is unfolded to both the left and right sides, and the roll folding portion 53 is unfolded without any trouble after that, and the knee receiving portion 32 is moved to the knee K (L, R ), and the knee receiving portion 32 can accurately receive the knee K (L, R).

In the embodiment, one side of the left and right folded parts 59L and 59R of the folded body, in the embodiment, the left folded part 59L having the longer length dimension LL in the horizontal direction has at least two folds 59a. , 59b are provided and folded over at the central portion 54, and a tape member 72 is provided as a connecting means.

That is, of the left and right folded portions 59L and 59R of the folded body 70, only one side, which needs to be restrained from projecting rearward, is provided as a connecting means prior to deployment in the left and right direction at the initial stage of expansion. A tape material 72 may be provided to form the folded body 70 .

In the case of the embodiment, when the airbag 30 is fully inflated, the mounting center MC, which is the center of the mounting portion 31 in the left-right direction, is aligned with the center line BL in the front-rear direction passing through the center of the knee receiving portion 32 in the left-right direction. It is configured to be shifted to one side of the direction (right side in the embodiment), and the left and right end side portions 55 and 56 of the roll folded portion 53 are arranged on the mounting center MC side in the central portion 54 of the roll folded portion 53. are folded to form a folded portion 59 (L, R). The folded portion 59L on the side where the tape material 72 as the connecting means in the folded body 70 is provided is the portion on the side (left side) of the center line BL deviated from the mounting center MC.

In such a configuration, when the airbag 30 is fully inflated, the mounting portion 31 is shifted in the left-right direction from the center line BL passing through the center of the knee receiving portion 32 in the left-right direction. In the end side portions 55 and 56, the left end side portion 55 on the side deviated away from the mounting center MC of the mounting portion 31 as one side is longer than the other end side portion 56 by the length dimension LL is long (LL>LR), if a tape material 72 as a connecting means is arranged at the folded portion 59L of the end side portion 55 of the long dimension LL on one side, the folded portion 59L can be It is possible to accurately suppress the rearward protrusion amount, deploy in the left-right direction, and then deploy and inflate so as to unroll the roll. Therefore, in the knee-protecting airbag device KA having such a configuration, the knee receiving portion 32 of the airbag 30 is arranged in front of the center KC in the left-right direction of the left and right knees KL, KR of the driver (passenger) M. Even if it is configured to be installed, it is suitable when the mounting center MC of the mounting portion 31 of the airbag 30 cannot be arranged in front of the knee center KC between the left and right knees KL and KR of the driver M.

Needless to say, the tape material 72 as a connecting means may be arranged not only on one of the left and right folded portions 59L of the folded body 70, but also on both left and right folded portions 59L and 59R.

As a connecting means, as in the embodiment, by wrapping the whole circumference along the front-rear direction of the first overlapped portion 60 and the distal end portion 61 of the folded portion 59L with a breakable tape material 72, The strength of the tape material 72 may be set so as to be broken when the first overlapped portion 60 and the distal end portion 61 are disconnected, thereby constituting the connecting means.

As a connecting means, as in the folding completion body 70A shown in FIG. 10, a fractable member is provided from the front surface 54a side of the central portion 54 on the outer peripheral side of the first fold 59a to the rear surface 61a side of the folded portion 59AL. The tape material 74 may be adhered and formed, and the tape material 74 may be set to have a strength that is broken when the first overlapped portion 60 and the distal end portion 61 are disconnected, thereby constituting the connecting means.

Specifically, in the folded body 70A, the front end portion 74a of the tape material 74 is adhered to the front surface 54a side of the central portion 54 near the first fold line 59a, and the rear end portion 74b is disposed on the tip side portion 61. It is attached and arranged on the rear surface 61a side beyond the tip 62a of the second overlapping portion 62 as. The tape material 74 is formed of the same material as the tape material 72 of the embodiment, and is adhered after the end side portion 55 is folded to form the folded portion 59AL. Other configurations of the folded body 70A are the same as those of the folded body 70 of the embodiment, including the right folded portion 59R.

In the folded body 70A, when the airbag 30 starts to inflate, the central portion 54 of the roll-folded portion 53 is inflated, and the left and right end portions 55 and 56 are also about to inflate. tries to expand left and right. At the folded portion 59AL which is long in the left-right direction and which is folded over at the center portion 54 with two folds 59a and 59b, the first fold 59a is unfolded and the first folded portion 60 is folded into the center portion 54. The folded state is maintained by a tape material 74 as a connecting means that connects the tip 62a side to the central portion 54 side until the tip side portion 61 on the tip side of the end side portion 55 is separated from the rear region BA of the end side portion 55. , the unfolding folded portion 59AL does not move rearward away from the first overlapping portion 60 side, and then the first overlapping portion 60 of the folded portion 59AL moves toward the rear area BA of the central portion 54 of the roll folded portion 53. If the tape material 74 is unfolded so as to open leftward in the left-right direction so as to detach from the tape material 74, the vicinity of the intermediate portion 74c of the tape material 74 is broken due to the subsequent behavior of separating from the first overlapped portion 60 on the side of the tip 62a. The second fold 59b is unfolded, and the folded portion 59AL itself unfolds the tip 62a side of the tip portion 61 to the left in the left-right direction. Therefore, even if the shin S (L, R) is close to the case 10, the central portion 54 of the roll-folded portion 53, the first overlapping portion 60 and the distal end side portion 61 that are developed in the left-right direction are not affected. The end side portion 55 having the . ).

Note that the folded portion 59R formed of the right end side portion 56 of the folded body 70A is in the same folded state as the folded body 70 of the embodiment, and the folded portion of the folded body 70 is folded. It is unfolded in the same manner as 59R, and together with the central portion 54 of the roll folding portion 53 and the folding portion 59AL, the folding of the roll folding is eliminated.

Further, as the connecting means, like the folded body 70B shown in FIG. The sheet material 76 is sewn to the front surface 54a side of the central portion 54 and to the rear surface 61a side of the folded portion 59BL. A portion to be broken 79 that is to be broken when the first overlapping portion 60 and the tip side portion 61 are disconnected may be disposed in the vicinity of the intermediate portion between the portions 78a to constitute the coupling means.

Specifically, on the side of the folded portion 59BL of the folded body 70B, the sheet material 76 is composed of two sheets, a front side portion 77 and a rear side portion. The rear side portion 78 is sewn to the front surface 54a side of the portion 54, and the rear end side of the rear side portion 78 is sewn to the rear surface 61a side beyond the tip 62a of the tip side portion 61 as a sewn portion 78a. Then, the ends of the front side portion 77 and the rear side portion 78 of the sheet material 76 are sewn together to form the sheet material 76, and the mutually sewn portions serve as breakable portions 79 to be broken. For the sheet material 76, the seamed portions 77a and 78a of the front side portion 77 and the rear side portion 78 are sewn to predetermined portions of the airbag 30 in advance, and the end side portion 55 is folded to form the folded portion 59AL. After that, a sewn portion 79 for sewing the ends of the front side portion 77 and the rear side portion 78 is formed and disposed. Other configurations of the folded body 70B are the same as those of the folded body 70 of the embodiment, including the folding portion 59R on the right side.

In the folded body 70B, when the airbag 30 starts to inflate, the central portion 54 of the roll-folded portion 53 is inflated, and the left and right end portions 55 and 56 are also about to inflate, resulting in the folded portions 59BL and 59R. tries to expand left and right. At the folded portion 59BL which is long in the left-right direction and is folded over at the central portion 54 with two folds 59a and 59b, the first fold 59a is unfolded and the first folded portion 60 is folded into the central portion 54. The folded state is maintained by the sheet material 76 as a connecting means in which the tip 62a side is joined to the central portion 54 side until the tip portion 61 on the tip side of the end side portion 55 is separated from the rear region BA of the end side portion 55. , the unfolding folded portion 59BL does not move rearward away from the first overlapping portion 60 side, and then the first overlapping portion 60 of the folded portion 59BL moves toward the rear region BA of the central portion 54 of the roll folded portion 53. If the sheet material 76 is unfolded so as to open leftward in the left-right direction so as to detach from the sheet material 76, the subsequent behavior of moving away from the first overlapped portion 60 on the side of the tip 62a causes the stitched portion 79 as the portion to be broken of the sheet material 76. The second fold 59b is unfolded, and the folded portion 59BL itself unfolds the tip 62a side of the tip portion 61 to the left in the left-right direction. Therefore, even if the shin S (L, R) is close to the case 10, the central portion 54 of the roll-folded portion 53, the first overlapping portion 60 and the distal end side portion 61 that are developed in the left-right direction are not affected. The end side portion 55 having the . ).

In this folded body 70B as well, the folded portion 59R made up of the right end side portion 56 is in the same folded state as the folded body 70 of the embodiment, and the folded body 70B is folded. It unfolds in the same manner as the heavy portion 59R, and together with the central portion 54 of the roll-folded portion 53 and the folded-over portion 59BL, the folding of the roll-fold is eliminated.

Further, the portion to be broken of the sheet material 76 may be formed by adhesion instead of sewing. The portion may be used as the portion to be broken.

Furthermore, as the connecting means, as in the folding completion body 70C shown in FIG. and a locking member 81 including locking heads 81a and 81b that are locked to the surface sides of the first overlapped portion 60 and the distal end portion 61, and the locking member 81 is formed from the first The coupling means may be configured to have a strength that separates the locking heads 81a and 81b from each other when the overlapped portion 60 and the distal end portion 61 are released from each other.

Specifically, on the side of the folded portion 59CL of the folded body 70C, a locking member 81 made of synthetic resin such as polypropylene is provided with a small-diameter shaft portion 81c penetrating the first overlapping portion 60 and the distal end portion 61. Enlarged locking heads 81a and 81b are provided on both ends of the locking head 81a, and the locking head 81a locks the surface (front surface) 60a of the first overlapping portion 60 on the side of the central portion 54, and locks. The head portion 81b is arranged so as to engage the rear surface 61a of the distal end portion 61 on the side remote from the central portion 54 . The locking member 81 is prepared in such a state that one head portion 81a or head portion 81b side is formed and the other head portion 81b or 81a is not formed, and the end side portion of the roll-folded portion 53 that is roll-folded is prepared. 55 is folded toward the central portion 54, the end portion of the shaft portion 81c where the locking head portions 81b and 81a are not provided at the first folded portion 60 folded at the second fold line 59b and the tip side portion 61. The end portion of the shaft portion 81c is expanded in diameter by, for example, melting treatment at the penetrating tip to form locking head portions 81b and 81a. The front surface 60a of the overlapping portion 60 on the central portion 54 side is locked, and the locking head portion 81b locks the rear surface 61a of the distal end portion 61 away from the central portion 54. As shown in FIG. Other configurations of the folded body 70C are the same as those of the folded body 70 of the embodiment, including the folding portion 59R on the right side.

In the folded body 70C, when the airbag 30 starts to inflate, the center portion 54 of the roll-folded portion 53 is inflated, and the left and right end portions 55 and 56 are also about to inflate, resulting in the folded portions 59CL and 59R. tries to expand left and right. At the folded portion 59CL that is long in the left-right direction and is folded over at the central portion 54 with two folds 59a and 59b, the first fold 59a is unfolded and the first overlapped portion 60 is folded into the central portion 54. The folded state is maintained by a locking member 81 as a coupling means that couples the tip 62a side to the first overlapped portion 60 on the central portion 54 side until the tip of the end side portion 55 is separated from the rear region BA of the end side portion 55. The leading end portion 61 on the side does not move rearward away from the unfolding folded portion 59CL on the side of the first folded portion 60 , and then the first folded portion 60 of the folded portion 59CL moves toward the roll folded portion 53 . If it is deployed so as to open leftward in the left-right direction so as to deviate from the rear region BA of the central portion 54, the behavior of moving away from the first overlapping portion 60 on the side of the distal end 62a thereafter causes the axis of the locking member 81 to move. The shaft portion 81c near the portion 81c, more specifically, near the locking head portions 81a and 81b where stress concentration is likely to occur is broken, and the locking head portions 81a and 81b are separated from each other. The folded portion 59CL itself unfolds the tip 62a side of the tip portion 61 to the left in the left-right direction. Therefore, even if the shin S (L, R) is close to the case 10, the central portion 54 of the roll-folded portion 53, the first overlapping portion 60 and the distal end side portion 61 that are developed in the left-right direction are not affected. The end side portion 55 having the . ).

Also in this folded body 70C, the folded portion 59R made up of the end side portion 56 on the right side is in the same folded state as the folded body 70 of the embodiment. It unfolds in the same manner as the heavy portion 59R, and unfolds the roll-folded portion together with the central portion 54 of the roll-folded portion 53 and the folded-over portion 59AL.

Furthermore, as the connecting means, as shown in the folding completion body 70D shown in FIG. 83 may be set to a fitting strength such that when the coupling between the first overlapping portion 60 and the distal end portion 61 is released, the fitting strength is set such that the folding portion 59DL is disengaged from the coupling means.

Specifically, in the folded body 70D, a cover 83 made of flexible cloth or the like has a bag shape with an opening 83a that covers the folded portion 59DL from the vicinity of the second fold 59b. The cover 83 is arranged so that when the end side portion 55 is folded to form the folded portion 59DL, the vicinity of the second fold 59b is fitted from the opening 83a to cover the folded portion 59DL. Other configurations of the folded body 70D are the same as those of the folded body 70 of the embodiment, including the folding portion 59R on the right side.

In the folded body 70D, when the airbag 30 starts to inflate, the central portion 54 of the roll-folded portion 53 is inflated, and the left and right end portions 55 and 56 are also about to inflate. tries to expand left and right. Then, at the folded portion 59DL that is long in the left-right direction and is folded over at the central portion 54 with two folds 59a and 59b, the first fold 59a is unfolded and the first overlapped portion 60 is folded into the central portion 54. The folded state is maintained by a cover 83 as a connecting means that wraps the first overlapped portion 60 and the tip side portion 61 from the vicinity of the second fold 59b until the end side portion 55 is removed from the rear area BA of the end side portion 55. The distal end portion 61 on the distal end side does not move rearward away from the unfolding folded portion 59DL on the side of the first folded portion 60 , and then the first folded portion 60 of the folded portion 59DL moves toward the roll folded portion 53 . If the cover 83 is deployed to open leftward in the left-right direction so as to deviate from the rear region BA of the central portion 54 of the second Since the coupling between the first folded portion 60 and the distal end portion 61 is released by deviating from the vicinity of the fold 59b, the second folded portion 59b is unfolded, and the folded portion 59DL itself becomes the distal end portion 61. The tip 62a side of is developed leftward in the left-right direction. Therefore, even if the shin S (L, R) is close to the case 10, the central portion 54 of the roll-folded portion 53, the first overlapping portion 60 and the distal end side portion 61 that are developed in the left-right direction are not affected. The end side portion 55 having the . ).

The folded portion 59R formed by the right end side portion 56 of the folded body 70D is also folded in the same folded state as the folded body 70 of the embodiment. It is unfolded in the same manner as 59R, and together with the central portion 54 of the roll folding portion 53 and the folding portion 59AL, the folding of the roll folding is eliminated.

In addition, the cover 83 has a substantially cylindrical shape by wrapping the first overlapping portion 60 and the distal end portion 61 from the vicinity of the second fold 59b, and has an opening on the second fold 59b side in addition to the opening 83a. may be provided.

Further, in the knee protection airbag device KA of the embodiment, the folded portion 59L of the folded body 70 is folded back at the first folded portion 60 and the second folded portion 59b to overlap the first folded portion 60. Although a case has been shown in which the second overlapped portion 62 is provided as the side portion 61, the third overlapped portion 62 is provided as in the folded bodies 70E and 70F of the airbag device KA shown in FIGS. 63 may be provided.

That is, in the folded portion 59EL of the folded body 70E shown in FIG. 14, the tip side portion 61 extending to the tip side of the end side portion 55 connected to the first overlapped portion 60 extends to the tip of the second fold 59b. A configuration comprising a second overlapped portion 62 having a third third fold 59c and extending from the second fold 59b to the third fold 59c, and a third overlapped portion 63 extending from the third fold 59c. there is The third overlapping portion 63 is arranged between the first overlapping portion 60 and the second overlapping portion 62 .

Further, in the folded body 70F shown in FIG. 15, the third overlapping portion 63 is overlapped on the side away from the first overlapping portion 60 in the second overlapping portion 62 overlapped on the first overlapping portion 60, are arranged.

In the folded bodies 70E and 70F as well, the tape material 72 serving as a connecting means wraps and connects the first overlapped portion 60 and the distal end side portion 61 in the same manner as in the embodiment. Of course, the bonding strength of the tape material 72 is reduced when the first folded portion 59a is unfolded and the first overlapped portion 60 is removed from the rear area BA of the central portion 54 when the inflation gas is introduced into the airbag 30. , so as to release the connection between the first overlapped portion 60 and the distal portion 61 .

In addition to the tape material 72 of the embodiment, the tape material 74, the sheet material 76, the locking member 81, and the cover 83 shown in FIGS. may

As for the first overlapped portion 60 and the tip end portion 61 that are joined by the joining means, in the folded body 70F shown in FIG. , and the third overlapping portion 63 may be simply overlapped with the second overlapping portion 62 without being coupled.

Furthermore, the tape materials 72 and 74, the sheet material 76, the locking member 81, and the cover 83, which serve as the above-described connecting means, may be used in a plurality of the same or in combination of different ones as appropriate. .

For example, the folded body 70G of the airbag 30 shown in FIG. 16 uses the tape material 72 and the locking member 81 as the connecting means. The tape material 72 is the same as that used for the folded body 70 shown in FIG. It is possible to break when the bond is released. The locking member 81 is the same as that used in the folded body 70C shown in FIG. The first overlapped portion 60 and the distal end portion 61 are provided with locking heads 81a and 81b that are disposed at both ends and are engaged with the surface sides of the first overlapped portion 60 and the distal end portion 61. When the coupling is released, the locking heads 81a and 81b can be separated from each other.

In the folded body 70G, when the airbag 30 starts to inflate, the long folded portion 59GL is folded until the first fold 59a is unfolded and the first folded portion 60 is removed from the rear region BA of the central portion 54. , the tip side portion 61 on the tip side of the end side portion 55 is maintained in a folded state by the tape material 72 and the locking member 81 as a coupling means that joins the tip portion 61 to the first overlapping portion 60 . , does not move rearward away from the unfolding folded portion 59GL from the first overlapping portion 60 side, and thereafter the first overlapping portion 60 of the folded portion 59GL moves to the rear region of the central portion 54 of the roll folded portion 53. If it is unfolded to open leftward in the left-right direction so as to detach from the BA, the tape material 72 is broken due to the subsequent behavior of separating from the first overlapping portion 60 on the side of the tip 62a, and the locking member 81 The vicinity of the shaft portion 81c, more specifically, the shaft portion 81c near the engaging head portions 81a and 81b where stress concentration is likely to occur is broken, and the engaging head portions 81a and 81b are separated from each other. Then, the second fold 59b is unfolded, and the folded portion 59GL itself unfolds the tip 62a side of the tip end portion 61 to the left in the left-right direction. Therefore, even if the shin S (L, R) is close to the case 10, the central portion 54 of the roll-folded portion 53, the first overlapping portion 60 and the distal end side portion 61 that are developed in the left-right direction are not affected. The end side portion 55 having the . ).

Since the folded body 70G uses both the tape material 72 and the locking member 81, the airbag 30 can be secured by adjusting the timing of breakage of both materials, compared to the use of the tape material 72 alone. It is possible to adjust the deployment direction in various ways.

A folded body 70H of the airbag 30 shown in FIG. 17 uses a tape material 72 and a tape material 74 as connecting means. The tape material 72 is the same as that used in the folded body 70 shown in FIG. It can be broken when the connection with 61 is released. The tape material 74 is the same as that used in the folded body 70A shown in FIG. 10, and extends from the front surface 54a side of the central portion 54 on the outer peripheral side of the first fold 59a to the rear surface 61a side of the folded portion 59HL. affixed to the When the coupling between the first overlapped portion 60 and the distal end portion 61 is released, it can be broken.

In the folded body 70H, when the airbag 30 starts to inflate, the long folded portion 59HL is folded until the first fold 59a is unfolded and the first folded portion 60 is separated from the rear region BA of the central portion 54. The folded state is maintained by the tape material 72 with the tip end side part 61 joined to the first overlapping part 60 and the tape material 74 with the tip 62a side joined to the center part 54 side, and the end side part 55 does not move rearward so as to leave the unfolding folded portion 59HL from the first folded portion 60 side, and then the first folded portion 60 of the folded portion 59HL moves to the roll folded portion. If the tape material 72 is unfolded so as to open leftward in the left-right direction so as to deviate from the rear area BA of the central portion 54 of the tape material 53, the tape material 72 is separated from the first overlapped portion 60 on the side of the tip 62a after that. Along with the rupture, the vicinity of the middle 74c of the tape material 74 is also ruptured. Then, the second fold 59b is unfolded, and the folded portion 59HL itself unfolds the tip 62a side of the tip portion 61 to the left in the left-right direction. Therefore, even if the shin S (L, R) is close to the case 10, the central portion 54 of the roll-folded portion 53, the first overlapping portion 60 and the distal end side portion 61 that are developed in the left-right direction are not affected. The end side portion 55 having the . ).

Since the tape material 72 and the tape material 74 are also used in the folded body 70H, the airbag 30 can be expanded by adjusting the timing when both of them are torn. It is possible to adjust the direction in various ways.

A folded body 70I of the airbag 30 shown in FIG. 18 uses a sheet material 76 and a locking member 81 as connecting means. The sheet material 76 is the same as that used for the folded body 70B shown in FIG. In addition, it is made of a flexible cloth or the like with both ends sewn together, and is near an intermediate portion between sewn portions 77a and 78a to the front surface 54a side of the central portion 54 and the rear surface 61a side of the folded portion 59IL. In addition, a breakable portion 79 that can be broken when the first overlapping portion 60 and the distal end portion 61 are disconnected is provided. The locking member 81 is the same as that used in the folded body 70C shown in FIG. The first overlapped portion 60 and the distal end portion 61 are provided with locking heads 81a and 81b that are disposed at both ends and are engaged with the surface sides of the first overlapped portion 60 and the distal end portion 61. When the coupling is released, the locking heads 81a and 81b can be separated from each other.

In this folded body 70I, when the airbag 30 starts to inflate, the long folded portion 59IL is folded until the first fold 59a is unfolded and the first folded portion 60 is removed from the rear region BA of the central portion 54. The folded state is maintained by the locking member 81 whose tip end portion 61 is joined to the first overlapping portion 60, and the sheet material 76 whose tip end portion 62a is joined to the center portion 54 side. 55 does not move rearward away from the unfolding folded portion 59IL on the side of the first overlapping portion 60, and thereafter the first overlapping portion 60 of the folded portion 59IL is rolled. If the portion 53 is unfolded so as to open leftward in the left-right direction so as to deviate from the rear area BA of the central portion 54 of the portion 53, the sheet material 76 moves away from the first overlapping portion 60 on the side of the tip 62a after that. At the same time, the shaft portion 81c of the locking member 81 near the shaft portion 81c, more specifically, the shaft portion 81c near the locking head portions 81a and 81b where stress concentration is likely to occur is broken, and the locking head portions 81a and 81b are broken. 81b sides are separated from each other. Then, the second fold 59b is unfolded, and the folded portion 59IL itself unfolds the tip 62a side of the tip portion 61 to the left in the left-right direction. Therefore, even if the shin S (L, R) is close to the case 10, the central portion 54 of the roll-folded portion 53, the first overlapping portion 60 and the distal end side portion 61 that are developed in the left-right direction are not affected. The end side portion 55 having the . ).

Also in this folded body 70I, since the sheet material 76 and the locking member 81 are used in combination, the airbag 30 can be released more easily by adjusting the timing of breakage of both of them, compared to using them alone. It is possible to adjust the deployment direction in various ways.

A folded body 70J of the airbag 30 shown in FIG. 19 uses a tape material 74 and a cover 83 as connecting means. The tape material 74 is the same as that used in the folded body 70A shown in FIG. 10, and extends from the front surface 54a side of the central portion 54 on the outer peripheral side of the first fold 59a to the rear surface 61a side of the folded portion 59HL. affixed to the When the coupling between the first overlapped portion 60 and the distal end portion 61 is released, it can be broken. The cover 83 is the same as that used for the folded body 70D shown in FIG. It is set so as to be separated from the folded portion 59JL when the coupling between the 60 and the tip side portion 61 is released.

In the folded body 70J, when the airbag 30 starts to inflate, the long folded portion 59JL is folded until the first fold 59a is unfolded and the first folded portion 60 is removed from the rear area BA of the central portion 54. The folded state is maintained by the tape material 74 that connects the tip 62a side to the central portion 54 side and the cover 83 that wraps the first overlapped portion 60 and the tip side portion 61 from the vicinity of the second fold 59b. As a result, the distal end portion 61 on the distal end side of the end side portion 55 does not move rearward away from the unfolding folded portion 59JL on the side of the first overlapping portion 60, and then moves to the first overlapping portion 60 of the folded portion 59JL. However, if it is unfolded to open leftward in the left-right direction so as to deviate from the rear area BA of the central portion 54 of the roll-folded portion 53, the behavior of moving away from the first overlapping portion 60 on the side of the tip 62a after that As a result, the tape material 74 near the middle 74c is broken, and the cover 83 is removed from near the second fold 59. As shown in FIG. Then, the second fold 59b is unfolded, and the folded portion 59JL itself unfolds the tip 62a side of the tip portion 61 to the left in the left-right direction. Therefore, even if the shin S (L, R) is close to the case 10, the central portion 54 of the roll-folded portion 53, the first overlapping portion 60 and the distal end side portion 61 that are developed in the left-right direction are not affected. The end side portion 55 having the . ).

Also in this folding completion body 70J, since the tape material 74 and the cover 83 are used in combination, the airbag 30 can be more easily controlled by adjusting the timing of breaking or detachment of both of them, compared to using them alone. It is possible to variously adjust the deployment direction of the.

Also, as the connecting means, the same one may be used in combination. For example, in the folded body 70K shown in FIG. 20, two pieces of the tape material 72 shown in FIG. 8 are used. Strictly speaking, two tape members 72K, 72K are arranged apart from each other as a tape member 72K having a narrower width than the tape member 72 in FIG.

As shown in FIGS. 20A to 20C, this folded body 70K unfolds in the same manner as the folded body 70 of FIG. However, in this folded body 70K, since a gap 73 is provided between the two tape materials 72K, 72K, the two tape materials 72K, 72K provided for the folded portion 59KL are separated from each other. Compared to the case where the tape material 72K is arranged in the entire region in the horizontal direction, the amount of the tape material 72K used can be reduced by the amount of the gap 73, and the weight can be reduced.

In the embodiment, the knee-protecting airbag device KA mounted on the front side of the driver as a passenger has been described, but the knee-protecting airbag device KA is mounted on the front side of the passenger in the front passenger seat as a passenger. You may apply this invention to.

In the knee protection airbag device KA of the embodiment, the case 10 is mounted on a vehicle with the projection opening 10a of the airbag 30 of the case 10 opened rearward. A knee-protecting airbag device may be provided on the lower end side of the instrument panel in front of the front passenger's seat so as to face the floor, with the projecting opening 10a of the case 10 directed downward.

DESCRIPTION OF SYMBOLS 10... (storage part) case, 30... airbag, 30a... upper part, 30b... lower part, 31... attachment part, 32... knee receiving part, 34... outer peripheral wall, 35... vehicle body side wall part, 36... occupant side wall part, 50... initial deployment body 50a... upper edge 50b... lower edge 52... roll-folded body 53... roll-folded part 54... center part 54a... front surface 54b... rear surface 55... (left) end side Part 56... (right) end side part 59 (L, R)... folded part 59AL, 59BL, 59CL, 59DL, 59EL, 59FL, 59GL, 59HL, 59IL, 59JL, 59KL... (left) folded part , 59a...first fold, 59b...second fold, 59c...third fold, 60...first overlapped portion, 61...tip side portion, 61a...rear surface, 62...second overlapped portion, 62a...tip, 63 ... third overlapping portion,
70, 70A, 70B, 70C, 70D, 70E, 70F, 70G, 70H, 70I, 70J, 70K... Folded body, 72, 72K... (Coupling means) Tape material, 74... (Coupling means) Tape material, 74a Front end portion 74b Rear end portion 74c Intermediate portion 76 (Coupling means) Sheet material 79 (To be broken portion) Sewing portion 81 (Coupling means) Locking member 81a (Front) engagement Stop head 81b (rear) locking head 81c Shaft 83 (coupling means) cover
G... inflation gas, BA... (center of roll folding part) rear area, MC... mounting center (between bolts 26a, 26a), ML... (mounting) center line, BL... center (of knee receiving part) line,
K (L, R) Knee, KC Knee center, S (L, R) Shin, M (driver/passenger) occupant, KA Knee protection airbag device.

Claims (14)

It is folded and stored in a storage portion arranged on the front and lower sides of the knees of a seated occupant, and when inflating gas flows in, it is deployed and inflated from the storage portion toward the rear upper side to the front side of the knees of the occupant. Equipped with an airbag for arranging the knee receiving part,
The airbag is
An outer peripheral wall connecting the outer peripheral edges of the occupant side wall portion on the occupant side and the vehicle body side wall portion on the vehicle body side,
As the inflation completion shape, a mounting portion is provided on the lower side as an upstream portion when the inflation gas flows in, and has a width dimension in the left-right direction that can be stored in the storage portion, and is attached to the storage portion. on the side, the knee receiving portion having a width dimension that is wider on both left and right sides than the mounting portion,
At the time of storage, the occupant side wall portion and the vehicle body side wall portion are overlapped and flattened, and the upper edge side of the knee receiving portion side is rolled so as to approach the lower edge side of the mounting portion side. The left and right end side portions of the folded roll-folded portion are formed as folded-over portions that are folded over the central portion near the center in the left-right direction of the roll-folded portion, and the folded portions are folded into the roll-folded portion. A knee-protecting airbag device having a configuration in which a folded body is formed by overlapping the central part of the body and the folded body is stored in the storage part,
The folded portion on at least one side in the left-right direction of the folded body,
folded over the central portion with at least two creases, and
A first overlapped portion from the first first fold to the second second fold on the central portion side, and a tip side portion that continues to the first overlapped portion and extends to the tip side of the end side portion. and are coupled by a coupling means and disposed,
When the inflating gas flows into the airbag, the first folded portion is unfolded and the first folded portion is removed from the rear region of the central portion. A knee-protecting airbag device, wherein the coupling strength of the coupling means is set so as to release the coupling with the knee-protecting airbag device. One of the left and right folding parts of the folded body is provided with at least two folds and folded over to the central part, and is provided with the connecting means. The knee protection airbag device according to claim 1. When the airbag is fully inflated, the mounting center, which is the center in the left-right direction of the mounting portion, is shifted to one side in the left-right direction from the center line in the front-rear direction passing through the center in the left-right direction of the knee receiving portion. , and
The end side portions on both left and right sides of the roll folded portion are folded toward the attachment center side in the central portion of the roll folded portion to form the folded portion,
3. The knee protection device according to claim 2, wherein the folded portion of the folded body on the side where the connecting means is provided is a portion on the side of the mounting center deviated from the center line. airbag device. 2. A knee-protecting airbag device according to claim 1, wherein said coupling means are arranged on both left and right sides of said folded body. The connecting means is formed by wrapping the entire periphery of the folded portion along the front-rear direction with a breakable tape material,
2. The knee-protecting airbag device according to claim 1, wherein the tape material is set to have a strength such that it is broken when the first overlapped portion and the distal portion are released. The connecting means is formed by attaching a breakable tape material from the front side of the central portion on the outer peripheral side of the first fold to the rear side of the folded portion,
2. The knee-protecting airbag device according to claim 1, wherein the tape material is set to have a strength such that it is broken when the first overlapped portion and the distal portion are released. The connecting means is formed of a flexible sheet material having both ends sewn to the front surface side of the central portion and the rear surface side of the folded portion on the outer peripheral side of the first fold,
The sheet material is broken in the vicinity of an intermediate portion between the stitched portions to the front side of the central portion and the rear side of the folded portion when the connection between the first overlapped portion and the tip side portion is released. 2. The knee-protecting airbag device according to claim 1, wherein a portion to be ruptured is provided. The coupling means includes a shaft penetrating the first overlapped portion and the distal end portion, and disposed at both ends of the shaft portion, and on the surface side of the first overlapped portion and the distal end portion. a locking head to be locked; and
3. The strength of the locking member is set so that the locking heads are separated from each other when the coupling between the first overlapped portion and the distal end portion is released. 2. The knee protection airbag device according to 1. the connecting means is formed of a cover that fits the folded portion so as to wrap the folded portion from the vicinity of the second fold;
2. A knee protection airbag according to claim 1, wherein said cover is set to have a fitting strength such that said cover is separated from said folded portion when the connection between said first overlapped portion and said tip portion is released. Device. The folded portion of the folded body includes the first folded portion and a second folded portion that is folded back at the second fold and overlaps the first folded portion as the tip side portion. 2. The knee protection airbag device according to claim 1, wherein the knee protection airbag device comprises: A tip end portion of the folded portion of the folded body extending to the tip end side of the end side portion connected to the first folded portion forms a third third fold ahead of the second fold. A configuration comprising a second overlap portion extending from the second fold to the third fold and a third overlap portion extending from the third fold,
2. The knee protection airbag device according to claim 1, wherein the third overlapping portion is arranged between the first overlapping portion and the second overlapping portion. A tip end portion of the folded portion of the folded body extending to the tip end side of the end side portion connected to the first folded portion forms a third third fold ahead of the second fold. A configuration comprising a second overlap portion extending from the second fold to the third fold and a third overlap portion extending from the third fold,
2. The third overlapped portion is overlapped on a side remote from the first overlapped portion of the second overlapped portion overlapped with the first overlapped portion. 2. The knee protection airbag device according to . The coupling means is
a tape material that wraps around the entire circumference of the folded portion in the front-rear direction and can be broken when the coupling between the first overlapping portion and the distal end portion is released;
A tape material that is attached from the front surface side of the central portion on the outer peripheral side of the first fold to the rear surface side of the folded portion and that can be broken when the coupling between the first overlapping portion and the tip side portion is released,
Both end sides are sewn to the front side of the central portion and the rear side of the folded portion on the outer peripheral side of the first fold, and the front side of the central portion and the rear side of the folded portion are sewn together. A sheet material having flexibility in which the vicinity of the intermediate portion between the sutured portions can be broken when the first overlapped portion and the distal end portion are decoupled;
A shaft penetrating through the first overlapped portion and the tip side portion, and engagements disposed at both ends of the shaft portion and engaged with surfaces of the first overlapped portion and the tip side portion. a locking head, and is separable so as to separate the locking heads from each other when the coupling between the first overlapped portion and the distal end portion is released;
a cover that fits the folded portion so as to cover the folded portion from the vicinity of the second fold, and is detached from the folded portion when the coupling between the first folded portion and the tip side portion is released;
2. The knee protection airbag device according to claim 1, wherein at least two of the same or different ones are combined. The coupling means is
A plurality of tape materials that wrap around the entire circumference of the folded portion in the front-rear direction and can be broken when the coupling between the first overlapped portion and the tip end portion is released,
14. The knee-protecting airbag device according to claim 13, wherein a plurality of said tape members are spaced apart in the left-right direction.

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