JP2022056008A - Air bag folding-completed body and folding method thereof - Google Patents

Abstract

To provide an air bag folding-completed body for knee protection, which can be efficiently and smoothly housed in front of an inclined air bag cover.SOLUTION: A folding-completed body 63 is configured such that a folded portion 51 is formed by folding an upper edge 47a side so as to approach a lower edge 47b side from a state where a reception side wall part 44 of a knee side of an air bag 40 and a vehicle body side wall part 45 of a vehicle body side are stacked to be developed flat, and a plurality of folded parts 65, 66 in which end sides extending from a center 64 of the folded portion to both left and right sides are folded with pleats along a cross direction of mountain fold and valley fold are formed to be sequentially stacked on a lower side of the center 64. The folded parts 65, 66 arranged on the lower side of the center have width sides LM1, LM2 in a cross direction smaller than a width size LF of the center 64 with front ends 65b, 66b sides roughly aligned with a vertical direction when seen from a horizontal direction.SELECTED DRAWING: Figure 2

Description

INDUSTRIAL APPLICABILITY The present invention is an airbag folding complete body and a folding method thereof, which are mounted on the lower front side of the driver's seat and the passenger seat in a vehicle and are used for a knee protection airbag device that protects the knees of an occupant. Regarding.

Conventionally, an airbag device for knee protection has been configured to include an airbag, a case, an inflator, and an airbag cover (see, for example, Patent Documents 1 and 2). The airbag is stored as a folded completed body in the storage area on the lower front side of the seated occupant's knee, and when expanding by inflowing expansion gas, the door of the airbag cover in the storage area is opened. It was pushed open and protruded diagonally upward and backward from the storage site to complete the expansion. The case, together with the airbag cover, constitutes the storage area for the folded airbag. The bottom wall is located on the front end side, and the side wall is a substantially square cylinder that extends rearward from the outer peripheral edge of the bottom wall. And, and an opening for protrusion of the inflatable airbag was arranged on the rear end side. The inflator was configured to be housed in the airbag so that the inflatable gas could be supplied to the airbag, and to be provided with a mounting bolt attached together with the airbag on the bottom wall side of the case. The airbag cover is a door that is mounted by arranging a door that is pushed by the airbag when inflated to open, covering the rear side of the protruding opening of the case, and arranging the lower end side from the upper end side to the front side. It was configured to have an arrangement wall portion. Further, the airbag has a widening width dimension in the left-right direction from the lower edge side to the upper edge side as an outer peripheral wall when expansion is completed, and the receiving side wall portion on the knee side and the vehicle body are configured to have substantially the same outer shape to each other. It was configured to include a side wall of the vehicle body on the side. To fold the airbag, from the state where the receiving side wall and the side wall of the vehicle body are overlapped and unfolded flat, fold the upper edge side closer to the lower edge side, and then fold the end side extending from the center part to both left and right sides. , Each can be stored in a case as a folded body folded to the center side (see Patent Document 1), or the end sides extending from the center to the left and right sides are divided into mountain folds and valley folds, respectively. In some cases, two folded portions folded with creases along the front-rear direction are stored in a case as a folded complete body (see Patent Document 2) that is folded in order toward the lower side of the central portion. The reason why the door arrangement wall of the airbag cover is tilted so that the lower end side is arranged forward from the upper end side is that the toes etc. are on the floor in front of the occupant's knees in the passenger compartment. This is to secure a space that can be moved freely.

Japanese Unexamined Patent Publication No. 2009-56980 Japanese Patent Application Laid-Open No. 2003-170801 (see C in FIG. 18)

However, when an attempt is made to store the folded body of Patent Document 2 in the conventional airbag device for knee protection described in Patent Document 1, two folded parts are formed below the central portion of the folded body. When the central parts of the folded parts are overlapped, that is, the three folded parts are overlapped in the vertical direction with the same width dimension in the front-back direction, so that the lower end side is arranged in the front side from the upper end side. There is a large gap on the front side of the upper end side of the door-arranged wall portion of the airbag cover arranged in an inclined manner, which wastes storage space. On the contrary, if the upper end side of the three folding parts is brought closer to the front side of the upper end side of the door arrangement wall part of the airbag cover so as not to cause waste, the two folding parts below it, In particular, the folded portion on the lower end side pushes out the lower end side of the door arrangement wall portion to the rear, and deforms the airbag cover.

The folded airbag completed body and the folding method thereof according to the present invention solve the above-mentioned problems, and the folded airbag that can be efficiently and smoothly stored in front of the inclined airbag cover is completed. The purpose is to provide the body and its folding method.

The folded body of the airbag according to the present invention is the airbag.
It is folded and stored in the storage area on the lower front side of the seated occupant's knee, and when the expansion gas flows in, the door of the airbag cover in the storage area is pushed open and protrudes diagonally upward to the rear side. , Configured for knee protection to complete expansion,
As the outer peripheral wall at the time of completion of expansion, a receiving side wall portion on the knee side and a vehicle body side wall portion on the vehicle body side having substantially the same outer shape are provided and configured.
From the state where the receiving side wall portion and the vehicle body side wall portion are overlapped and unfolded flat, a folded portion is formed so that the upper edge side approaches the lower edge side, and both left and right sides from the central portion of the folded portion. A plurality of folded portions are arranged on the lower side of the central portion by making creases along the front-rear direction of the mountain fold and the valley fold, respectively. The folded body of the airbag
A plurality of the folded portions arranged on the lower side of the central portion
Seen from the left and right
Align the front end side roughly in the vertical direction,
It is characterized in that the width dimension in the front-rear direction is smaller than the central portion of the folded portion.

In the folded body of the airbag according to the present invention, a plurality of vertically overlapping folded portions below the central portion of the folded portion make the width dimension in the front-rear direction smaller than the central portion of the folded portion. Therefore, the rear end of the folded portion can be arranged so as to be displaced forward from the central portion of the folded portion above the folded portion, and the lower end side of the airbag cover is inclined so as to be arranged forward. A plurality of vertically overlapping folding portions can be arranged on the front surface side of the door arrangement wall portion to be arranged without interfering with each other. Of course, since the plurality of folded portions that overlap vertically are arranged so that the front end side is substantially along the vertical direction, the airbag device such as an inflator that supplies the expansion gas to the airbag is located on the front side thereof. The components can be arranged efficiently in a small space.

Therefore, in the folded airbag body according to the present invention, the airbag can be efficiently and smoothly stored in front of the inclined airbag cover, and a sufficient space under the feet of the occupant can be sufficiently secured.

Then, the plurality of folded portions arranged on the lower side of the central portion are
It is desirable that the width dimension in the front-rear direction is reduced in order from the central portion to the lower folded portion.

In such a configuration, the rear ends of the plurality of folded portions can be arranged so as to be shifted downward in order toward the front side, and when the folded completed body is mounted, the lower end side of the airbag cover can be arranged. The rear ends of the plurality of folded parts can be arranged substantially evenly on the front side of the door arrangement wall portion that is arranged so as to be inclined forward, and wasteful space can be created. Since it does not occur, the plurality of folded portions of the airbag can be arranged more efficiently and smoothly.

Further, in the folding method of the folded body of the airbag according to the present invention, the airbag is used.
It is folded and stored in the storage area on the lower front side of the seated occupant's knee, and when the expansion gas flows in, the door of the airbag cover in the storage area is pushed open and protrudes diagonally upward to the rear side. , Configured for knee protection to complete expansion,
As the outer peripheral wall at the time of completion of expansion, a receiving side wall portion on the knee side and a vehicle body side wall portion on the vehicle body side having substantially the same outer shape are provided and configured.
From the state where the receiving side wall portion and the vehicle body side wall portion are overlapped and unfolded flat, the upper edge side is folded so as to approach the lower edge side to form a folded portion, and both left and right sides from the central portion of the folded portion. An airbag formed by stacking a plurality of folded portions, each of which is folded along the front-back direction of a mountain fold and a valley fold, on the lower side of the central portion in order. It is a folding method of the completed body,
After the receiving side wall portion and the vehicle body side wall portion are overlapped and unfolded flatly, the upper edge side is folded so as to approach the lower edge side to form the folded portion, and then the folded portion is formed.
Fold the upper edge of the left-right edge side of the folded portion to the lower edge side with diagonal creases so that the folding width of the left-right edge side is wider than that of the central portion.
Then, the end sides extending from the central portion of the folded portion to the left and right sides are creases along the front-rear direction of the mountain fold and the valley fold, respectively, and the folded portion is on the lower side of the central portion. It is characterized by folding so as to arrange.

In the folding method according to the present invention, the first folding step of forming a folded portion in which the receiving side wall portion and the vehicle body side wall portion are overlapped and unfolded flatly so that the upper edge side approaches the lower edge side. After, before the third folding process, in which the end side in the left-right direction from the central part is made a crease along the front-back direction of the mountain fold and the valley fold, and the folded part is folded in order on the lower side of the central part. In addition, diagonal creases are made on the upper edge of the folded portion formed in the first folding step on the left-right edge side so as to widen the folding width on the left-right edge side from the central portion side. Therefore, a second folding step of folding is provided on the lower edge side. That is, after the second folding step, the upper edge itself extending from the central portion in the folding portion of the first folding step toward the end side in the left-right direction approaches the lower edge side toward the end edge side in the left-right direction. Then, the folded portion itself from the central portion to the end side in the left-right direction after the first folding step makes the width dimension in the front-rear direction approach the lower edge side in order toward the end edge side. , Make it smaller. Therefore, in the subsequent third folding step, creases along the front-back direction of the mountain fold and the valley fold are made on the end side in the left-right direction from the central part, and they are overlapped in order on the lower side of the central part. When folding, the folding part itself that goes downward from the central part folds in a state where the upper edge side (which becomes the rear end side at the time of mounting) approaches the lower edge side (front end side) in order, and also the lower edge side (the lower edge side (the front end side)). At the time of mounting, the front end side) will be folded along the vertical direction.

Therefore, in the folding method of the folded completed body of the airbag according to the present invention, even if the folded completed body gradually reduces the width dimension in the front-rear direction of the plurality of folded portions, that is, that is, Even if the shape is such that multiple folds are folded in the vertical direction while shifting the rear end side forward in order, simply by adding the second folding step to fold them so as to make diagonal creases, Can be formed.

Then, in this folding method, the width dimension in the left-right direction when the end side extending from the central portion to the left and right sides is mountain-folded is the left-right direction of the storage portion for accommodating the folded completed body. Equivalent to the width dimension and
The diagonal creases when folding the left and right edge sides of the folded portion to the lower edge side with diagonal creases so that the folding width of the left and right edge sides is wider than that of the center side, respectively. It is desirable that the starting point position of is near the fold of the mountain fold.

In such a folding method, since the folded completed body has the same width dimension in the left-right direction as the width dimension in the left-right direction of the storage portion, it is possible to easily store the folded body in the storage portion. can. In addition, since the starting point of the diagonal fold is near the fold of the mountain fold, the rear end side of the folded portion below the central portion of the folded portion is brought closer to the rear end side of the central portion. In this state, it can be arranged in order by shifting it to the front side, and the folded body can be arranged closer to the front side of the door arrangement wall of the airbag cover, and the door can be arranged. The storage space on the front side of the arrangement wall can be effectively used.

It is a schematic vertical sectional view which shows the vehicle mounting state of the knee protection airbag device which uses the folding complete body of the airbag of one Embodiment which concerns on this invention. It is an enlarged schematic vertical sectional view of the airbag device in which the folded body of the airbag of the same embodiment is used, and corresponds to the vicinity of the II-II portion of D of FIGS. 3 and 5. It is a schematic cross-sectional view of the airbag device in which the folded body of the airbag of the same embodiment is used. It is a figure explaining the folding process of the airbag of the same embodiment in order. It is a figure explaining the folding process of the airbag of the same embodiment in order, and shows the process after FIG. FIG. 3 is a schematic vertical sectional view of a knee protection airbag device in which a folded body of a comparative example is used.

Hereinafter, an embodiment of the present invention will be described. As shown in FIG. 1, the knee protection airbag device 10 using the folded body 63 of the airbag 40 according to the embodiment is a steering column in front of the driver's seat. It is mounted below 1. The steering column 1 is configured to include a steering shaft (not shown) to which a steering wheel 4 steered by the driver M as a occupant is assembled, and a column tube 2 covering the steering shaft. On the rear side, the column cover 3 is provided. It is covered with. The column cover 3 protrudes rearward from the instrument panel (hereinafter, appropriately abbreviated as instrument panel) 5, and the knee protection airbag device 10 is located at the lower portion 6 of the instrument panel 5 below the column cover 3. , Is installed.

As shown in FIGS. 1 to 3, the knee protection airbag device 10 includes a case 13, an airbag cover 20, an inflator 30, and an airbag 40.

The case 13, together with the airbag cover 20, constitutes a storage portion 11 of the folded airbag 40 (folded complete body 63), and is made of sheet metal and has a substantially rectangular plate-shaped bottom arranged on the front end side. A wall portion 14 and a substantially square tubular side wall portion 15 extending rearward from the outer peripheral edge of the bottom wall portion 14 are provided, and an expansion opening 18 for an inflatable airbag 40 is arranged on the rear end side. It is set up. A through hole 14a for passing a mounting bolt 33 extending from the inflator 30 is arranged in the bottom wall portion 14, and the upper wall portion 25a and the lower wall portion 25b of the side wall portion 15 are arranged forward on the rear end side. A plurality of locking hooks 16 projecting so as to be inverted are arranged. Each locking hook 16 is inserted into a locking hole 26 provided in the side wall portion 25 described later of the airbag cover 20 to lock the side wall portion 25.

A plurality of mounting brackets (not shown) are provided on the bottom wall portion 14 and the side wall portion 15 in order to mount the airbag device 10 on the bracket extending from the instrument panel hose.

The airbag cover 20 is made of a synthetic resin such as polyolefin, and is provided with a door portion 22 (U, D) that is pushed by the airbag 40 during expansion to open, so that the rear side of the protruding opening 18 of the case 13 is provided. The door-arranged wall portion 21 for covering and the side wall portion 25 having a substantially square cylinder shape extending forward from the periphery of the door portion 22 (U, D) in the door-arranged wall portion 21 are provided. The door arrangement wall portion 21 is mounted so as to be inclined so that the lower end 21b side is arranged on the front side from the upper end 21a side so that a space on the floor side under the feet of the driver M can be secured on the rear side. The door. The door-arranged wall portion 21 is surrounded by the lower portion 6 of the instrument panel 5 on the upper side and the left and right sides on the rear surface 21d side, and is surrounded by the undercover 7 on the lower side.

The door portions 22U and 22D each have a substantially square plate shape, and when pushed by the expanding airbag 40, the surrounding thin-walled fractured portion 24 is broken, and hinges arranged on the vertical edge side. It is configured to open up and down with the portion 23 as the center of rotation.

Further, the upper and lower wall portions 25a and the lower wall portion 25b of the side wall portion 25 are provided with locking holes 26 into which the locking hook 16 of the case 13 is inserted. The left wall portion 25c and the right wall portion 25d of the side wall portion 25 are the case 13 when the upper and lower upper wall portions 25a and the lower wall portion 25b of the side wall portion 25 are locked to the locking hook 16 of the case 13. The side wall portion 15 is arranged so as to cover the outside of the left wall portion 15c and the right wall portion 15d.

The inflator 30 includes a substantially cylindrical main body 31 in which a gas discharge portion 31a for discharging the expansion gas G is arranged on the right end side, and a substantially square tubular sheet metal retainer 32 for holding the main body 31. It is composed of. Two mounting bolts 33 are projected forward from the retainer 32. These mounting bolts 33 project from the through hole 45a described later of the airbag 40 in a state where the retainer 32 is housed in the airbag 40, and further penetrate the through hole 14a of the bottom wall portion 14 of the case 13. By fastening the nut 34, the airbag 40 is attached and fixed to the bottom wall portion 14 of the case 13, and the inflator 30 is attached and fixed to the bottom wall portion 14 of the case 13.

When the nut 34 is fastened to each mounting bolt 33, the main body 31 housed in the retainer 32 is pushed by the convex portion 14b provided on the bottom wall portion 14 of the case 13 to the rear of the retainer 32. Since it is pressed against the inner peripheral surface side of the main body 31, the main body 31 is also firmly held by the retainer 32.

Further, a lead wire 36 for inputting an operation signal of the inflator 30 is coupled to the main body 31 on the end surface side away from the gas discharge portion 31a.

The airbag 40 is stored as a folded completed body 63 in the storage portion 11 on the front lower side of the knee K of the seated driver M, and when the expansion gas G is flowed in and expanded, the storage portion 11 is stored. The door portion 22 (U, D) of the airbag cover 20 of the above is pushed open and protrudes diagonally upward from the storage portion 11 to complete the expansion, and the width dimension of the upper portion 41 in the left-right direction from the lower portion 42 is set. It is configured to be spread out to protect the knee K (see FIGS. 1 and 4). The airbag 40 is configured as an outer peripheral wall 43 when expansion is completed by widening the width dimension in the left-right direction from the lower edge 42a side to the upper edge 41a side (WU> WD) and having substantially the same outer shape to each other. It is configured to include a receiving side wall portion 44 on the knee side and a vehicle body side wall portion 45 on the vehicle body side. Since the airbag 40 projects diagonally upward and rearward from the storage portion 11 in the vehicle-mounted state to complete the expansion, the upper edge 41a is also the trailing edge of the airbag 40, and the lower edge 42a is , Also the leading edge.

The airbag 40 is formed of a woven fabric such as polyester or polyamide, and has a base cloth having a shape in which a receiving side wall portion 44 and a vehicle body side wall portion 45 are connected on the upper edge 41a side. It is formed by folding on the 41a side and sewing the overlapping outer peripheral edges to each other. On the lower edge 42a side of the side wall portion 45 of the vehicle body, a through hole 45a through which the two mounting bolts 33 are inserted and an insertion hole 45b into which the main body 31 of the inflator 30 is inserted are opened (see FIGS. 2 to 4). ).

When the airbag 40 is folded to form the folded complete body 63, first, as shown in A of FIG. 4, the initially deployed air in which the receiving side wall portion 44 and the vehicle body side wall portion 45 are overlapped and flatly deployed. Form the bag 47. Then, as the first folding step, as shown in A and B of FIG. 4, the creases H1 and H2 in the left-right direction are provided so that the upper edge 47a (41a) side approaches the lower edge 47b (42a) side. The first folding body 50, which is provided with a folding portion 51 which is rolled and folded, is formed. In the case of the embodiment, the upper edge 47a side is arranged on the side of the side wall portion 45 of the vehicle body and folded, and the folding portion 51 is formed from the folding area 48 on the upper edge 47a side of the initial deployment airbag 47. Since the inflator 30 is arranged in the non-folding area 49 provided with the through hole 45a, the inflator 30 is not folded so as to narrow the dimension in the front-rear direction.

Then, as shown in B and C of FIG. 4, as the second folding step, the upper edge (trailing edge) away from the lower edge 47b side of the initial deployment airbag 47 at the folding portion 51 of the first folding body 50. On the left and right edge 51c and 51d sides on the 51a side, diagonal creases CL and CR are provided so as to widen the folding width BW on the left and right edge 51c and 51d sides from the center side, and the upper edge 51a is provided. While the side is brought closer to the lower edge 51b side, the diagonally folded portion 60 (L, R) folded on the side of the side wall portion 45 of the vehicle body is provided to form the second folded body 55. In this case, the left side portion 53 and the right side portion 54 extending left and right from the central portion 52 in the left-right direction of the folding portion 51 of the first folding body 50 are on the lower edge (leading edge) 51b side of the folds CL and CR. The folded portions 53b, 54b (diagonal folded portions 60L, 60R) of the upper edges (trailing edges) 51a of the folds CL and CR are overlapped on the main body portions 53a and 54a, and the second folded body 55 is folded. The tatami mat portion 56 is formed.

After that, as a third folding step, as shown in C of FIG. 4 and A to D of FIG. 5, the central portion in the left-right direction of the folding portion 56 of the second folding body 55 on the side of the receiving side wall portion 44. The left side portion 58 and the right side portion 59 on the left and right sides extending from 57 to the left and right sides are the mountain fold fold CM (L, R) and the valley fold fold CV (L, R) along the front-rear direction, respectively. If the folding portions 65 (L, R) and 66 (L, R) are provided so as to be stacked in order on the lower side of the central portion 57, the third folding body, that is, the folding The completed body 63 can be formed (see D in FIGS. 2 and 5).

The width dimension WM in the left-right direction of the folded complete body 63 folded by the mountain fold fold CM (L, R) (see D in FIG. 5) is the width dimension WS of the storage portion 11, that is, the storage portion. It is the same as the width dimension WS (see FIG. 3) between the left wall portion 15c and the right wall portion 15d in the side wall portion 15 of the case 13 of 11.

Further, the fold CM (L, R) of the mountain fold substantially coincides with the intersection of the upper edges 51a of the diagonal folds CL and CR, that is, the starting points CL0 and CR0 of the folds CL and CR. It is set to do.

In the folded body 63, the central portion 57 in the left-right direction of the folded portion 56 of the second folded body 55 constitutes the central portion 64 of the folded completed body 63, and is located on the left and right immediately below the central portion 64. , The original side folding portions 65L and 65R composed of the left side portion 58 and the original portions 58a and 59a of the right side portion 59 in the folding portion 56 of the second folding body 55 are folded, and further, the original side folding portion 65L. , 65R, the end side folding portions 66L and 66R including the tip portions 58b and 59b of the left side portion 58 and the right side portion 59 in the folding portion 56 of the second folding body 55 are folded.

Then, after the second folding process before the third folding process, the diagonal folding folded at the folds CL and CR causes the end edges 51c and 51d in the left-right direction from the central portion 52 of the folding portion 51 in the first folding process. The upper edge 51a itself extending toward the lower edge 51b approaches the lower edge 51b side toward the end edges 51c and 51d in the left-right direction, and heads toward the end side in the left-right direction from the central portion 52 after the first folding step. The folding portion 56 itself makes the upper edge 51a side closer to the lower edge 51b side in order as the width dimension in the front-rear direction toward the end side, and the width dimension LF on the central portion 57 side to the end edge 51c. , The width dimension LB on the 51d side is reduced. Therefore, in the subsequent third folding step, the creases CM (L, R) and CV (L, If R) is attached and the folded portions 65 and 66 are folded so as to be overlapped on the lower side of the central portion 57 in order, the folded portions 65 and 66 themselves extending downward from the central portion 57 have the width dimensions LM1 and LM2 in the front-rear direction before and after the central portion 64. The width dimension in the direction is smaller than the LF (see FIG. 2), and the upper edges 65a and 66a (the rear end side at the time of mounting) are brought closer to the lower edges 65b and 66b (front end side) in order. The lower edges 65b and 66b (the front end side at the time of mounting) are folded in a vertical direction.

In such folding of the airbag 40, the mounting bolt 33 is projected from the through hole 45a in advance, and the retainer 32 is inserted into the airbag 40 to form the folded complete body 63. Then, after the folded body 63 is formed, the folded body 63 is wrapped with a wrapping sheet 70 for preventing the folding completed body 63 (see FIG. 2).

Then, before storing in the case 13, the main body 31 of the inflator 30 is inserted into the retainer 32 through the insertion hole 45b, the lead wire 36 is connected to the main body 31, and the mounting bolt 33 protrudes from the through hole 14a. The folded body 63 is arranged on the bottom wall portion 14 side in the case 13, and the nut 34 is fastened to the mounting bolt 33. The terminal of the lead wire 36 is discharged to the outside of the case 13 from the take-out recess provided in the side wall portion 15 of the case 13.

Then, the terminal side (not shown) of the lead wire 36 is connected to the lead wire (not shown) on the vehicle body side for inputting the operation signal of the airbag device 10, and the mounting bracket (not shown) of the case 13 is attached to a predetermined bracket on the vehicle body side. At the same time, the side wall portion 25 of the airbag cover 20 is arranged on the outer peripheral side of the side wall portion 15 of the case 13, and each locking hook 16 is inserted into the locking hole 26 to form an upper wall portion 25a and a lower wall portion 25b. By connecting and then assembling the undercover 7 to the vehicle body side, the airbag device 10 can be mounted on the front lower side of the knee K of the driver M of the vehicle.

After that, when an operation signal is input to the main body 31 of the inflator 30, the expansion gas G is discharged from the gas discharge portion 31a of the inflator 30, and the airbag 40 causes the expansion gas G to flow in to expand and the airbag. The door portions 22U and 22D of the door arrangement wall portion 21 of the cover 20 are pushed open up and down to project diagonally upward and rearward from the protrusion opening 18 of the case 13 to complete the expansion.

Then, in the folded body 63 of the airbag 40 of the embodiment, two folded portions 65 (L, R) and 66 (L, R) that are vertically overlapped below the central portion 64 of the folded portion are formed. Since the width dimensions LM1 and LM2 in the front-rear direction are smaller than the width dimensions LF in the front-rear direction of the central portion 64 (LF> LM1, LM2), the rear ends 65a and 66a of the folded portions 65 and 66 are designated. A door arrangement wall that can be arranged so as to be displaced forward from the rear end 64a of the central portion 64 above the central portion 64 and is arranged so as to be inclined so that the lower end 21b side of the airbag cover 20 is arranged forward. Two folding portions 65, 66 that overlap vertically can be arranged on the front surface 21c side of the portion 21 without interfering with each other. Of course, since the two folded portions 65 and 66 that overlap vertically are arranged so that the front ends 65b and 66b sides are substantially along each other in the vertical direction, the expansion gas G is supplied to the airbag 40 on the front side thereof. The components of the airbag device 10 such as the inflator 30 can be efficiently arranged in a small space.

Therefore, in the folded body 63 of the airbag 40 of the embodiment, it can be efficiently and smoothly stored in front of the inclined airbag cover 20, and sufficient space under the feet of the occupant M can be secured.

Further, in the folded body 63 of the airbag 40 of the embodiment, the two folded portions 65, 66 arranged on the lower side of the central portion 64 are directed toward the lower folded portions 65, 66 from the central portion 64. Then, the width dimensions LM1 and LM2 in the front-rear direction are sequentially reduced (LF> LM1> LM2).

Therefore, in the embodiment, the rear ends 65a and 66a of the two folded portions 65 and 66 can be arranged so as to be shifted downward in order toward the front side, and when the folded completed body 63 is mounted, the two folded portions 65 and 66 can be arranged. Two folded portions 65a and 66a are provided on the front end 21c side of the door arrangement wall portion 21 which is arranged so as to be inclined so that the lower end 21b side of the airbag cover 20 is arranged forward. The two folding portions 65 and 66 of the airbag 40 should be arranged more efficiently and smoothly because they can be arranged so as to be substantially evenly approached and do not create wasted space. Can be done.

The folded body 103 folded without the second folding step is in the stored state as shown in FIG. In this folded body 103, roll folding is performed so that the upper edge 47a of the initial deployment airbag 47 shown in FIGS. 4A and 4 approaches the lower edge 47b, and then the left and right sides of the roll folding portion are front and rear. Fold it along the mountain fold and valley fold along the direction, and form the two folds 101 and 102 on the tip side of each fold so that they overlap below the central part 100 in the left-right direction of the roll fold part. It was done. Further, when forming the roll folding portion, in the case of the illustrated example, the folds H1, H2, and H3 along the left-right direction are set once more than in the case of the embodiment.

In the folding completed body 103 of this comparative example, when the central portion 100 of the roll folding portion is combined, the three folding portions 100, 101, 102 overlap in the vertical direction with the same width dimension L0 in the front-rear direction. When the folded body 103 is mounted on the vehicle, the upper end 21a of the door arrangement wall portion 21 in the airbag cover 20 is arranged so as to be inclined so that the lower end 21b side is arranged toward the front side from the upper end 21a side. There is a large gap 104 on the front side of the side, which wastes storage space.

Further, the folded complete body 103 of this comparative example has three folds H1, H2, and H3 as roll folds that bring the upper edge 47a of the initial unfolded airbag 47 closer to the lower edge 47b. On the other hand, in the folded complete body 63 of the embodiment, since the folded portion 51 of the roll fold has two folds H1 and H2 as the folds of the roll fold, the expansion gas G is allowed to flow in. When inflating, the number of folds in the roll folds is small, so the roll folds can be quickly eliminated, and as a result, the time from the start of expansion of the airbag to the completion of expansion can be shortened and quickly. In addition, the knee K of the occupant M can be protected.

Then, in the folding method of the folded body 63 of the airbag 40 of the embodiment, the upper edge 47a side is opened from the state where the receiving side wall portion 44 of the airbag 40 and the vehicle body side wall portion 45 are overlapped and unfolded flat. After folding so as to approach the lower edge 47b side to form the folded portion 51, the upper edges 51a on the left and right end edges 51c and 51d of the folded portion 51 are respectively left and right from the central portion 52 side. With diagonal creases CL and CR so as to widen the folding width BW on the edge 51c and 51d sides, fold it toward the lower edge 47b, and then fold it on both the left and right sides from the central portion 57 of the folding portion 56. Fold the extending ends 58 and 59 to the lower side of the central part 57 with creases CM (L, R) and CV (L, R) along the front-back direction of the mountain fold and the valley fold, respectively. The portions 65 (L, R) and 66 (L, R) are folded so as to be arranged.

Therefore, in the folding method of the embodiment, the folding portion is folded so that the upper edge 47a side approaches the lower edge 47b side from the state where the receiving side wall portion 44 and the vehicle body side wall portion 45 are overlapped and unfolded flat. After the first folding step of forming 51, the folds CM (L, R), CV (L, Before the third folding step of folding the folding portions 65 and 66 in order on the lower side of the central portion 57 with R) attached, the left-right edge 51c of the folding portion 51 formed in the first folding step, The upper edge 51a on the 51d side is diagonally folded CL, CR (in other words, from the upper edge 51a side) so as to widen the edge width 51c in the left-right direction and the folding width BW on the 51d side from the center side, respectively. A second folding step is provided in which a linear crease CL, CR) that expands to the lower edge 51b side and intersects the edge 51c, 51d side is provided and folded toward the lower edge 51b side. That is, after the second folding step, the upper edge 51a itself extending from the central portion 52 in the folding portion 51 of the first folding step toward the end portions 53 and 54 in the left-right direction becomes the end edges 51c and 51d in the left-right direction. As it approaches the lower edge 51b side, the folding portion 56 itself from the central portion 52 after the first folding step toward the end portions 53 and 54 in the left-right direction has the width dimension in the front-rear direction. The upper edge 51a side is brought closer to the lower edge 51b side in order toward the edges 51c and 51d (width dimension LF> width dimension LB), and the size is reduced. Therefore, in the subsequent third folding step, creases CM and CV along the front-rear direction of the mountain fold and the valley fold are attached to the end portions 58 and 59 in the left-right direction from the central portion 57, respectively, and the central portion 57 is provided. When the folded portions 65, 66 themselves are folded downward from the central portion 57 (64), the upper edges 65a, 66a side (which is the rear end side at the time of mounting) are sequentially folded downward. The edges 65b and 66b (front end side) are folded close to each other, and the lower edges 65b and 66b (front end side at the time of mounting) are folded along the vertical direction.

Therefore, in the folding method of the folded complete body 63 of the embodiment, the folded completed body 63 reduces the width dimensions LM1 and LM2 of the two folded portions 65 and 66 in the front-rear direction in order toward the lower side. That is, even if the two folded portions 65 and 66 are folded in the vertical direction while shifting the rear end 65a and 66a sides in order, diagonal creases CM and CV are attached. It can be easily formed by simply adding the second folding step.

Further, in the embodiment, the width dimension WM in the left-right direction when the end portions 58 and 59 extending from the central portion 57 to the left and right sides are respectively mountain-folded, the left and right sides of the storage portion 11 for accommodating the folded body 63. It is the same as the width dimension WS in the direction. Further, diagonal creases CL and CR are attached to the left and right edge sides of the folded portion so that the folding widths BW on the left and right end edges 51c and 51d are wider than those on the center side, respectively, and the lower edge 51b. The starting point positions CL0 and CR0 of the diagonal folds CL and CR when folding sideways are set to be near the fold CM of the mountain fold.

Therefore, in the folding method of the embodiment, since the folded folding completed body 63 has the width dimension WM in the left-right direction equal to the width dimension in the left-right direction of the storage portion 11, it is stored in the storage portion 11. Can be easily performed. Further, since the starting points CL0 and CR0 of the diagonal folds CL and CR are located near the fold CM of the mountain fold, the folded portions 65 and 66 below the central portion 57 (64) of the folded portion 56. The rear ends 65a and 66a can be arranged so as to be sequentially shifted to the front side in a state where the rear ends 65a and 66a are close to the rear end 64a side of the central portion 64, and the door arrangement wall portion of the airbag cover 20 can be further arranged. The folded body 63 can be arranged close to the front surface 21c side of the door 21, and the storage space on the front surface 21c side of the door arrangement wall portion 21 can be effectively used.

By the way, if the starting points CL0 and CR0 of the diagonal folds CL and CR are located on the center side in the left-right direction from the fold CM (L, R) of the mountain fold, the rear end 64a of the central portion 64 is located. The forward displacement of the folded portions 65, 66 on the rear ends 65a, 66a side becomes large, and the distance between the rear ends 65a, 66a of the folded portions 65, 66 and the front surface 21c of the door arrangement wall portion 21 becomes large. It gets bigger. Further, if the starting point positions CL0 and CR0 of the diagonal folds CL and CR are located on the left and right end edges 51c and 51d side of the mountain fold fold CM (L, R), the rear of the central portion 64. The forward deviation of the folded portions 65, 66 from the ends 64a to the rear ends 65a, 66a side becomes smaller, and the rear ends 65a, 66a of the folded portions 65, 66 are on the front surface 21c side of the door arrangement wall portion 21. There is a risk of getting too close to.

In the folded body 63 of the embodiment, the two folded portions 65 and 66 are arranged below the left and right sides of the central portion 64, but in the third folding step, the folds along the front-rear direction are formed. Further, in addition, the left and right end portions 58 and 59 sides of the folding portion 56 in the second folding step may be folded so that three or more folding portions are arranged below the central portion 64.

Further, in the embodiment, the folded body 63 of the airbag 40 of the airbag device 10 for protecting the knee mounted in the front and lower parts of the driver's seat has been described, but the present invention is mounted in the front and lower parts of the passenger seat. It can also be applied to the folded body of the airbag of the airbag device for knee protection.

10 ... Airbag device for knee protection, 11 ... Storage part (of airbag), 13 ... Case, 20 ... Airbag cover, 22 (U, D) ... Door part, 40 ... Airbag, 41a, 47a, 51a ... (Trailing edge) Upper edge, 42a, 47b, 51b ... (Front edge) Lower edge, 43 ... Outer wall, 44 ... Receiving side wall, 45 ... Body side wall, 51 ... Folding part, 51c, 51d ... Edge edge , 52, 57, 64 ... Central part, 53, 58 ... Left side part, 54, 59 ... Right side part, 63 ... Folded body, 64a, 65a, 66a ... Rear end, 64b, 65b, 66b ... Front end, 65 ( L, R), 66 (L, R) ... Folded part,
LF, LM1, LM2 ... Width dimension (in the front-back direction of the fold), BW ... (diagonal fold) fold width, CL, CR ... (diagonal) fold, CL0, CR0 ... starting position, CM (L, R) ... (mountain fold) fold, CV (L, R) ... (valley fold) fold, WU ... (upper edge side of airbag) width dimension, WD ... (under airbag) Width dimension (on the veranda), M ... (occupant) driver, K ... knee, G ... expansion gas.

Claims (4)

The airbag
It is folded and stored in the storage area on the lower front side of the seated occupant's knee, and when the expansion gas flows in, the door of the airbag cover in the storage area is pushed open and protrudes diagonally upward to the rear side. , Configured for knee protection to complete expansion,
As the outer peripheral wall at the time of completion of expansion, a receiving side wall portion on the knee side and a vehicle body side wall portion on the vehicle body side having substantially the same outer shape are provided and configured.
From the state where the receiving side wall portion and the vehicle body side wall portion are overlapped and unfolded flat, a folded portion is formed so that the upper edge side approaches the lower edge side, and both left and right sides from the central portion of the folded portion. A plurality of folded portions are arranged on the lower side of the central portion by making creases along the front-rear direction of the mountain fold and the valley fold, respectively. The folded body of the airbag
A plurality of the folded portions arranged on the lower side of the central portion
Seen from the left and right
Align the front end side roughly in the vertical direction,
A folded body of an airbag characterized in that the width dimension in the front-rear direction is smaller than the central portion of the folded portion. A plurality of the folded portions arranged on the lower side of the central portion
The folded body of the airbag according to claim 1, wherein the width dimension in the front-rear direction is sequentially reduced from the central portion toward the folded portion below. The airbag
It is folded and stored in the storage area on the lower front side of the seated occupant's knee, and when the expansion gas flows in, the door of the airbag cover in the storage area is pushed open and protrudes diagonally upward to the rear side. , Configured for knee protection to complete expansion,
As the outer peripheral wall at the time of completion of expansion, a receiving side wall portion on the knee side and a vehicle body side wall portion on the vehicle body side having substantially the same outer shape are provided and configured.
From the state where the receiving side wall portion and the vehicle body side wall portion are overlapped and unfolded flat, the upper edge side is folded so as to approach the lower edge side to form a folded portion, and both left and right sides from the central portion of the folded portion. An airbag formed by stacking a plurality of folded portions, each of which is folded along the front-back direction of a mountain fold and a valley fold, on the lower side of the central portion in order. It is a folding method of the completed body,
After the receiving side wall portion and the vehicle body side wall portion are overlapped and unfolded flatly, the upper edge side is folded so as to approach the lower edge side to form the folded portion, and then the folded portion is formed.
Fold the upper edge of the left-right edge side of the folded portion to the lower edge side with diagonal creases so that the folding width of the left-right edge side is wider than that of the central portion.
Then, the end sides extending from the central portion of the folded portion to the left and right sides are creases along the front-rear direction of the mountain fold and the valley fold, respectively, and the folded portion is on the lower side of the central portion. A method of folding an airbag completed body, which is characterized by folding so as to be arranged. The width dimension in the left-right direction when the end side extending from the center portion to both the left and right sides is mountain-folded is equal to the width dimension in the left-right direction of the storage portion for storing the folded body.
The diagonal creases when folding the left and right edge sides of the folded portion to the lower edge side with diagonal creases so that the folding width of the left and right edge sides is wider than that of the center side, respectively. The method for folding a folded air bag according to claim 3, wherein the starting point position of the air bag is near the fold of the mountain fold.

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