JP2021154941A - Airbag device - Google Patents

Abstract

To provide an airbag device configured so that an airbag and an inflator can be easily assembled to an attachment base, while securing gas sealability.SOLUTION: The airbag device comprises an attachment base 30 that is attached to a loading site while holding an airbag 10 and an inflator 25, and a bracket 50. The airbag comprises a cylindrical inflow port part 12 through which gas for inflation flows into a main body part 11, where fin parts 16 and 17 are provided in the inflow port part. The attachment base and the bracket comprise half-split cylindrical parts 33 and 53 that can cover the inflow port part of the airbag having the inflator inserted thereinto, and gripping parts 35, 55, 36 and 56 that can grip the fin parts of the airbag mutually. The gripping parts of the attachment base and of the bracket are overlapped to shape irregularities mutually and integrally while gripping the fin parts and are connected to each other by caulking joined parts 65 subjected to plastic deformation processing for forming undercut parts 66 which restrict mutual separation.SELECTED DRAWING: Figure 6

Description

The present invention relates to an airbag device mounted on a vehicle, and more particularly to an airbag device capable of easily assembling an airbag and an inflator to a mounting base while ensuring gas sealability.

Conventionally, for example, in an airbag device for knee protection, an airbag that inflows an expansion gas and expands from a folded state, an inflator that supplies the expansion gas to the airbag, and an airbag and an inflator are held. Then, it was configured to include a case as a sheet metal mounting base to be mounted on the mounting site, and a sheet metal bracket for mounting the airbag and the inflator to the case (see, for example, Patent Document 1). The inflator had a substantially cylindrical shape for discharging the expansion gas, and the bracket had a substantially cylindrical shape for holding the inflator. On the outer peripheral side of the bracket, a plurality of bolts for attaching the airbag and the inflator to the case were projected so as to penetrate the airbag and the case. In this airbag device, with the bolt protruding from the airbag, the bracket is stored in the airbag, the airbag is folded, and then the bolt is passed through the through hole in the bottom wall of the case to the case. The folded body of the airbag is stored in the case while protruding outward, and the inflator is inserted from the side wall of the case into the bracket inside the airbag through the insertion hole of the airbag, and then the inflator is inserted. By fastening the nut to the bolt protruding outside the case, the bracket is brought closer to the bottom wall side of the case, and the inflator inserted in the tubular bracket is pressed against the bottom wall side of the case, and the inflator Was attached to the case, and the inflator and the airbag were assembled to the case by pressing the portion of the airbag between the bracket and the bottom wall of the case against the bottom wall of the case to fix it.

JP-A-2018-167996

However, in the conventional airbag device, the inflator is inserted and arranged from the side wall of the case through the insertion hole of the airbag and into the bracket housed in the airbag, so that the inflator is provided in the airbag. It is necessary to take measures against leakage of expansion gas from the peripheral edge of the insertion hole, and there is a problem in that the gas sealability is good and the inflator and the airbag are assembled to the case as a mounting base. Furthermore, by using multiple bolts and nuts, the airbag and inflator are assembled to the case as the mounting base, which increases the number of parts, increases cost and weight, and further makes it possible to use multiple bolts. It was difficult to assemble easily because it was necessary to fasten the nuts.

The present invention solves the above-mentioned problems, and an object of the present invention is to provide an airbag device capable of easily assembling an airbag and an inflator to a mounting base while ensuring gas sealability.

In the airbag device according to the present invention,
A sheet metal mounting base that holds the airbag and the inflator and is mounted on the mounting site.
A sheet metal bracket that attaches the inflator to the mounting base,
It is an airbag device that is configured with
The inflator has a substantially cylindrical shape in which a gas discharge portion for discharging expansion gas is arranged on the tip side.
The airbag is formed of a flexible sheet material,
The main body that expands by inflowing expansion gas from the folded state,
It is provided with a cylindrical inflow port portion that communicates with the main body portion, inserts the tip end side of the inflator, and allows expansion gas from the inflator to flow into the main body portion.
It is configured to include fins protruding on both sides of the inflow port in the direction orthogonal to the axis on the outer peripheral surface side of the inflow port.
The mounting base and the bracket
Approximately half the circumference of the outer circumference of the air bag into which the inflator is inserted can be wrapped around the outer circumference of the substantially cylindrical inflow port portion, and approximately half the circumference of the outer circumference of the inflow port portion can be covered. Half-split cylinder and
A plate-shaped holding portion capable of mutually holding the fin portions on both sides of the inlet portion of the airbag, and a plate-shaped holding portion.
With
In a state where the sandwiching portion between the mounting base and the bracket sandwiches the fin portions on both sides of the inflow port portion, the fin portions are overlapped and integrally formed with each other, and mutual separation is regulated. It is characterized in that it is connected to each other by a caulking joint portion formed by plastic deformation processing to form an undercut portion.

In the airbag device according to the present invention, an inflator is inserted into the inlet portion of the folded airbag with the gas discharge portion side at the head, and then the inlet portion into which the inflator is inserted is inserted into the half-split cylinder portion of the mounting base. While storing, place the fins on both sides of the inflow port on the holding part of the mounting base. Then, while mounting the inflator into which the inflator is inserted so as to cover the half-split cylinder of the bracket, the bracket holding portions are also mounted on the fins on both sides of the inflow port, and in that state, the mounting base Plastic deformation processing is performed to form an undercut portion that regulates mutual detachment while forming irregularities on the sandwiched portion between the bracket and the bracket, and a caulking joint is formed between the sandwiched portions between the mounting base and the bracket. Then, the holding portions of the mounting base and the bracket are connected to each other, and the inflator and the airbag can be assembled to the mounting base. That is, by joining the holding portions of the mounting base and the bracket to each other, the inflator is sandwiched between the half-split cylinders of the mounting base and the bracket in a state of being inserted into the inlet portion of the airbag, and becomes the mounting base. It is fixed. In addition, the inflow port of the airbag is sandwiched between the inner peripheral surfaces of the half-split cylinders of the mounting base and the bracket with the inflator inserted, and the entire circumference of the inner peripheral surface becomes the outer peripheral surface of the inflator. In the state of pressure contact, it has good gas sealing properties and is connected to the inflator. Of course, when the main body of the airbag expands due to the expansion gas from the inflator, the fins on both sides of the inflow port are sandwiched between the holding parts of the mounting base and the bracket, so that the inlet of the airbag Since the portion is firmly held by the mounting base without coming off, the airbag can be expanded and expanded while being stably held by the mounting base.

The plastic deformation processing for forming such a caulking joint is performed by lance lock (see JP-A-6-281011, JP-A-2006-38105, JP-A-2019-143716) and Tox-caulking (see JP-A-2019-143716). 2002-310109 (see JP-A-2002-310109) can be exemplified. That is, in these processes, the planned processing portion of the stacked sheet metal (steel plate) is fixed by the press mold holder and the presser mold, and the punch through which the presser mold is inserted is applied to the scheduled machining portion so as to be recessed. , The stacked sheet metal is plastically deformed together, and the movable presser mold on the holder side is opened, the punch is further pressed against the holder side, the planned machining part is compressed, and the undercut part (locking protrusion) is placed on the plastically deformed part. ) Is formed, and the undercut portion is processed to a size that locks the undercut portion with the corresponding locking portion of the plastic deformation portion, which can be easily performed by using a predetermined press die.

Therefore, in the airbag device according to the present invention, the airbag and the inflator can be easily assembled to the mounting base while ensuring the gas sealability.

Then, in the airbag device according to the present invention, the caulking joint between the holding portions of the mounting base and the bracket may be formed by plastic deformation processing by a lance lock.

That is, if the plastic deformation processing that connects the holding parts of the mounting base and the bracket to each other is a lance lock, the planned processing part (plastic deformation part) in the holding part between the mounting base and the bracket and the fin part of the airbag at the time of processing. ), Since a certain cutting part is generated on both edges, wrinkles near the planned processing part of the fin part are reduced, the influence on the inflow port part can be suppressed, and good gas sealing property is ensured. Easy to do.

Further, in the airbag device according to the present invention, locking legs are formed on both sides of the half-split cylinder portion of the bracket.
The locking legs are, respectively.
Penetration provided in the holding portion of the mounting base and the fin portion of the airbag so as to project from both side portions of the half-split cylinder portion so as to be substantially orthogonal to the holding surface of the holding portion of the bracket. The shaft that penetrates the hole and
A locking claw that can be bent from the tip of the shaft portion in a direction away from the half-split cylinder portion of the bracket to lock the peripheral edge of the through hole on the back surface side of the holding portion of the mounting base.
Is configured with
The through hole between the holding portion of the mounting base and the fin portion of the airbag has a wide opening through which the locking claw can be inserted and the wide opening in a direction along the axial direction of the half-split cylinder portion. It is configured to include a narrow opening that is connected to the portion, allows the shaft portion to be inserted, and prevents the locking claw from being inserted.
The caulking joint portion may be formed in a state in which the locking leg portion of the bracket is moved from the wide opening portion of the through hole to the narrow opening portion.

In such a configuration, even if the holding portion of the bracket tries to separate from the holding portion of the mounting base, the locking leg portion of the bracket locks the locking claw on the back surface side of the holding portion of the mounting base. Even if the caulking joint is loosened, the behavior of the bracket holding part from peeling off from the mounting base can be accurately prevented, and the mounting base ensures gas sealability, and the airbag and inflator Can be held stably.

It is a schematic vertical sectional view which shows the vehicle-mounted state of the airbag device for knee protection of 1st Embodiment which concerns on this invention. It is a schematic perspective view seen from the upper surface side of the airbag device of 1st Embodiment. It is a schematic vertical sectional view of the airbag device of 1st Embodiment, and is a schematic vertical sectional view along the left-right direction. It is a schematic exploded perspective view of the airbag device of 1st Embodiment. It is a top view of the state in which the airbag of 1st Embodiment is deployed flat. It is a schematic vertical sectional view of the airbag device of 1st Embodiment, and corresponds to the vicinity of the VI-VI part of FIG. It is a figure explaining the state which the caulking joint part between the holding part of a mounting base and a bracket is formed by a lance lock. It is the schematic perspective view of the airbag device of 2nd Embodiment. It is a schematic exploded perspective view of the airbag device of 2nd Embodiment. It is a top view of the state in which the airbag of the 2nd Embodiment is unfolded flat. It is a schematic vertical sectional view of the airbag device of 2nd Embodiment, and corresponds to the vicinity of the XI-XI part of FIG. It is a schematic vertical sectional view of the airbag device of 2nd Embodiment, and corresponds to the vicinity of the XII-XII part of FIG. It is a figure explaining the state which the caulking joint part between the holding part of a mounting base and a bracket is formed by tox caulking.

Hereinafter, the airbag device according to the embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the airbag device 9 according to the first embodiment is for knee protection and is in front of the passenger seat. It is mounted on the lower side of the instrument panel (appropriately abbreviated as instrument panel) 6, specifically, below the grab box 7 arranged on the lower side of the instrument panel 6. The grab box 7 includes a box main body 7a and a door portion 7b that closes the rear of the box main body 7a, and the door portion 7b is arranged so as to be openable so as to rotate the upper edge side rearward. Further, an undercover 8 is arranged below the grab box 7, and a door arrangement wall portion 71 of the airbag cover 70 described later in the airbag device 9 is arranged in the opening 8a of the undercover 8. , The airbag device 9 is mounted on the lower side in front of the passenger seat.

As shown in FIGS. 1 to 6, the airbag device 9 inflows an expansion gas G (see FIG. 3) so as to protect the knees of an occupant seated in the passenger seat, and the airbag 10 expands from the folded state. The inflator 25 that supplies the expansion gas G to the airbag 10, the mounting base 30 that holds the airbag 10 and the inflator 25 and is mounted on the front lower side of the passenger seat as a mounting site, and the inflator 25 are mounted. It is configured to include a bracket 50 to be attached to the base 30 and an airbag cover 70 to cover the folded airbag 10 and be held by the attachment base 30.

The front-back, up-down, and left-right directions in the present specification substantially correspond to the vehicle-mounted state, and as shown in FIGS. 1 to 3, the substantially rectangular holding plate of the mounting base 30. The long direction of the portion 31 will be the left-right direction, the short direction will be the front-back direction, and the orthogonal direction of the holding plate portion 31 will be the up-down direction. Incidentally, in FIGS. 3 and 4, a cross-sectional view and an exploded perspective view in a state of being turned upside down are shown.

As shown in FIGS. 1, 4 and 5, the airbag 10 communicates with the main body 11 that expands by inflowing the expansion gas G from the folded state and the main body 11, and the inflator 25 is communicated with the opening 15 of the terminal. A tubular (cylindrical in the embodiment) inflow port portion 12 is provided so that the tip 25a side of the inflator 25a is inserted to allow the expansion gas G from the inflator 25 to flow into the main body portion 11.

Further, the airbag 10 is configured to include fin portions 16 and 17 projecting on both sides of an axially orthogonal direction VD orthogonal to the axial direction ID of the inflow port portion 12 on the outer peripheral surface 13 side of the inflow port portion 12. ..

The airbag 10 is a suture portion 10a (FIG. 5) in which a sheet material (base cloth for a bag) made of a woven fabric woven with a flexible polyamide or other thread is folded in half and the overlapped outer peripheral edges are sewn together. (See) is provided to form the main body portion 11 and the inflow port portion 12.

Further, the main body 11 of the airbag 10 is arranged in the bag arrangement 32 on the surface (inner side surface) 31a side of the holding plate 31 described later of the mounting base 30 in a folded state, and the flow extends from the main body 11. In the inlet portion 12, a half portion (base side) 13a of the outer peripheral surface 13 is housed in the half-split cylinder portion 33 described later of the holding plate portion 31.

The fin portions 16 and 17 are arranged as the seam allowance 10b of the inflow port portion 12 in the holding portions 35 and 36 described later on both sides of the half-split cylinder portion 33 of the holding plate portion 31. Further, the portion 18 indicated by the alternate long and short dash line on the fin portions 16 and 17 is a scheduled processing portion 18 for forming the caulking joint portion 65 described later, and in the case of the first embodiment, the number of the caulking joint portions 65 is increased. Correspondingly, three are arranged in the fin portion 16 and two are arranged in the fin portion 17.

As shown in FIGS. Has been done. A connector 29 for connecting an operation signal line LW for inputting an operation signal is arranged on an end surface of the inflator 25 on the base portion 25b side (see FIG. 3).

As shown in FIGS. 2 to 4 and 6, the mounting base 30 is made of sheet metal such as a steel plate and includes a holding plate portion 31 having a substantially rectangular plate shape. Mounting bracket portions 42 (L, R) that are mounted and fixed to the bracket 2 extending from the above are arranged and configured.

The holding plate portion 31 is provided with a bag arranging portion 32 for arranging the main body portion 11 side of the folded airbag 10 on the surface (inner side surface) 31a side, and is slightly forward side from the center in the front-rear direction. A half-split cylinder portion 33 for accommodating the inflow port portion 12 of the airbag 10 into which the inflator 25 is inserted is arranged.

Approximately half of the inflow port portion 12 in the direction orthogonal to the axis (upper half in the vehicle-mounted state) is housed in the half-split cylinder portion 33, and the inner peripheral surface 33a is the outer peripheral surface 13 of the inflow port portion 12 of the airbag 10. The base side 13a for approximately half the circumference of the upper side is stored so as to be pressure-welded. When the inner peripheral surface 33a is pressed against the outer peripheral surface 13 of the inflow port portion 12, the inner peripheral surface 14 of the inflow port portion 12 is strongly pressed against the outer peripheral surface 26a side of the main body portion 26 of the inflator 25 to form an inflator. A plurality of beads 33b are formed to further improve the gas sealing property of the inflow port portion 12 covering the 25. Further, an opening 33c is formed on the right end side of the half-split cylinder portion 33 so that the operation signal line LW extending from the connector 29 of the inflator 25 can be discharged.

Further, on both front and rear sides of the half-split cylinder portion 33 of the holding plate portion 31, plate-shaped holding portions 35 and 36 on which the fin portions 16 and 17 on both sides of the inflow port portion 12 of the airbag 10 are placed are arranged. .. Also in the sandwiching portions 35 and 36, a scheduled processing portion 38 for forming a caulking joint portion 65, which will be described later, is arranged as a portion 38 indicated by the alternate long and short dash line. That is, on the sandwiching portion 35 side, corresponding to the three caulking joints 65, the scheduled processing portions 38 are arranged at three locations, and on the sandwiching portion 36 side, the two caulking joints 65 correspond. The planned processing portions 38 are arranged at two locations.

A plurality of connecting recesses 45, which are connected and held by inserting a connecting convex portion 76, which will be described later, of the airbag cover 70, are opened on the front and rear edge sides of the holding plate portion 31 beyond the holding portions 35 and 36.

Further, mounting holes 42a are penetrated through the mounting bracket portions 42 (L, R) on both the left and right sides of the holding plate portion 31. Then, each mounting bracket portion 42 (L, R) has an airbag device 9 by fixing a bolt 3 (see the two-dot chain line in FIG. 1) penetrating the mounting hole 42a to the bracket 2 on the body 1 side with a nut 4. Will be mounted on the lower front side of the passenger seat below the grab box 7.

As shown in FIGS. It is configured to include connecting wall portions 75 (F, B) extending upward from the edge. A thin-walled planned rupture portion 73 along the left-right direction is disposed on the door arrangement wall portion 71, and when the main body portion 11 of the airbag 10 expands, the planned rupture portion 73 is ruptured and the door opens on both front and rear sides. Parts 72 (F, B) are arranged. The front and rear connecting wall portions 75 (F, B) are provided with a plurality of connecting convex portions 76 that are inserted and locked into the connecting concave portions 45 of the mounting base 30 at the upper ends.

Like the mounting base 30, the bracket 50 is made of sheet metal and includes a half-split cylindrical half-split cylinder portion 53 and flat plate-shaped holding portions 55 and 56 extending from the half-split cylinder portion 53 to both front and rear sides. It is configured.

The half-split cylinder portion 53 covers substantially the lower half of the inlet portion 12 of the airbag 10 into which the inflator 25 is inserted in the direction orthogonal to the axis (it is the lower side when mounted on a vehicle), and the inflow port portion 12 The inner peripheral surface 53a has a curved shape that can be pressure-welded to the lower surface side (bracket side) 13b of the outer peripheral surface 13. Then, when the inflow port portion 12 is pressed against the outer peripheral surface 13 of the inner peripheral surface 53a, the inner peripheral surface 14 of the inflow port portion 12 is strongly pressed against the outer peripheral surface 26a of the main body portion 26 of the inflator 25. A plurality of beads 53b are formed to further improve the gas sealing property of the inflow port portion 12 covering the inflator 25.

Further, as shown by the alternate long and short dash line, the sandwiching portions 55 and 56 are also provided with the scheduled machining portions 58 for forming the caulking joint portion 65, which will be described later. In the case of the first embodiment, the sandwiching portions 55 and 56 are arranged so as to be divided by leaving a space 57 for each scheduled machining portion 58, and corresponds to the number of scheduled machining portions 58 (caulking joint portion 65). Then, three holding portions 55 are arranged on the front edge side of the bracket 50, and two holding portions 56 are arranged on the rear edge side of the bracket 50.

The caulking joint portion 65 of the first embodiment is formed by a lance lock. The lance lock is performed by using the press mold 100 shown by the alternate long and short dash line in FIGS. 7A and 7, and at the time of processing, for example, on the fin portion 16 side (the same applies to the fin portion 17 side). As shown in A of FIG. 7, the scheduled machining portions 38, 58, 18 of the holding portions 35, 55, which are overlapped with the fin portions 16 in between, are formed by the movable presser die 102 and the presser die 104 on the holder 101 side of the press die 100. Then, as shown in B of FIG. 7, the punch 103 through which the pressing die 104 is inserted is applied to the planned processing portions 38, 58, 18 so as to be recessed, and the overlapping holding portions 35, 55. The movable retainer 102 on the holder 101 side is opened, and the punch 103 is further pressed against the holder 101 to compress and deform the planned machining portions 38, 58, 18 and the plasticity on the recessed side. An undercut portion (locking protrusion) 66 is formed at the deformed portion 65a, and the undercut portion 66 is processed to a size that locks the undercut portion 66 with the corresponding locking portion 67 of the plastic deformation portion 65b on the non-recessed side. It is a thing.

The caulking joint portion 65 by the lance lock is shifted so that the holding portions 35, 55 and the fin portion 18 are sheared, that is, the undercut portion 66 side is sheared from the locking portion 67 side. Therefore, fracture surfaces (shear surfaces) 68 are formed on both edges of the plastic deformation portion 65a.

Two such caulking joints 65 are arranged on the fin portion 17 side of the airbag 10, and on the fin portion 16 side on the side away from the main body portion 11, the tensile strength of the main body portion 11 during expansion is increased. Therefore, the number is increased from the fin portion 17 side, and three are arranged.

Explaining the assembly work of the airbag device 9 of the first embodiment, first, the main body 11 of the airbag 10 is folded and wrapped with a wrapping material (not shown) for preventing folding. Then, the inflator 25 is inserted into the inflow port portion 12 of the airbag 10 from the gas discharge portion 27 side. Then, while arranging the main body 11 of the folded airbag 10 on the bag arranging portion 32 of the mounting base 30, the inflow port portion 12 of the airbag 10 into which the inflator 25 is inserted is half of the holding plate portion 31 of the mounting base 30. It is housed in the split cylinder portion 33, and the expanded fin portions 16 and 17 are placed on the holding portions 35 and 36 of the mounting base 30. Next, the half-split cylinder portion 53 of the bracket 50 is put on the inflow port portion 12 of the airbag 10 into which the inflator 25 is inserted, and the holding portions 55 and 56 of the bracket 50 are covered with the fin portions 16 and 17 of the airbag 10. In that state, it is set on the press mold 100, and the overlapped scheduled machining portions 58, 18, 38 are plastically deformed by the lance lock to form the scheduled machining portions 58, 18, 38. When the caulking joint portion 65 is formed, the mounting base 30 in which the fin portions 16 and 17 are sandwiched, the sandwiching portions 35 and 55 of the bracket 50 and the sandwiching portions 36 and 56 are joined to each other, and the inflator 25 and the airbag are joined. The airbag device 9 can be assembled because the 10 and the 10 have good gas sealing properties and are assembled to the mounting base 30. Then, after assembling the airbag device 9, the operation signal line LW is connected to the connector 24 on the base portion 20b side of the inflator 25, and the mounting bracket portions 42 (L, R) of the mounting base 30 are bolted. If the airbag device 9 is attached to the bracket 2 on the body 1 side by using the 3 and the nut 4, the airbag device 9 can be mounted on a predetermined mounting portion below the grab box 7.

If the inflator 25 is activated after the airbag device 9 is mounted, the expansion gas G is discharged from the gas discharge port 27a of the gas discharge unit 27, and the airbag 10 is the expansion gas that has flowed in through the inflow port portion 12. The main body 11 is expanded and expanded by G, and the doors 72F and 72B of the airbag cover 70 are pushed open to be arranged on the front side of the knee of the passenger in the passenger seat.

Then, in the airbag device 9 of the first embodiment, the inflator 25 is inserted into the inflow port portion 12 of the folded airbag 10 with the gas discharge portion 27 side at the head, and then the inflator portion 25 into which the inflator 25 is inserted. 12 is housed in the half-split cylinder portion 33 of the mounting base 30, and the fin portions 16 and 17 on both sides of the inflow port portion 12 are placed on the holding portions 35 and 36 of the mounting base 30, and the inflator 25 is further inserted. While mounting the inflow port portion 12 so as to cover the half-split cylinder portion 53 of the bracket 50, the holding portions 55 and 56 of the bracket 50 are also mounted on the fin portions 16 and 17 on both sides of the inflow port portion 12. In this state, plastic deformation that forms an undercut portion 66 that regulates mutual detachment while forming irregularities on the sandwiching portions 35, 55 of the mounting base 30 and the bracket 50 and the sandwiching portions 36, 56 of each other. If lance lock is performed as a process to form a caulking joint 65 between the holding portions 35, 55 between the mounting base 30 and the bracket 50 and between the holding portions 36, 56, the mounting base 30 and the bracket 50 can be connected. The sandwiching portions 35, 55 and the sandwiching portions 36, 56 are connected to each other, and the inflator 25 and the airbag 10 can be assembled to the mounting base 30.

That is, in the first embodiment, the inflator 25 is inserted into the inflow port portion 12 of the airbag 10 by joining the sandwiching portions 35, 55 of the mounting base 30 and the bracket 50 to each other and the sandwiching portions 36, 56 to each other. In this state, the mounting base 30 and the bracket 50 are sandwiched between the half-split cylinder portions 33 and 53 and fixed to the mounting base 30. Further, the inflow port portion 12 of the airbag 10 is sandwiched between the inner peripheral surfaces 33a and 53a of the half-split cylinder portions 33 and 53 of the mounting base 30 and the bracket 50 with the inflator 25 inserted, and is inside. In a state where the entire circumference of the peripheral surface 14 is in pressure contact with the outer peripheral surface 26a of the inflator 25, the peripheral surface 14 is connected to the inflator 25 with good gas sealing property. Of course, when the main body 11 of the airbag 10 is expanded by the expansion gas G from the inflator 25, the fins 16 and 17 on both sides of the inflow port 12 are the holding portions 35 and 36 between the mounting base 30 and the bracket 50. , 55, 56 are sandwiched between each other, so that the inlet portion 12 of the airbag 10 is firmly held by the mounting base 30 without coming off, so that the airbag 10 is stable to the mounting base 30. The main body 11 can be expanded and expanded while being held.

Further, as described above, in the plastic deformation processing for forming the caulking joint portion 65, for example, on the fin portion 16 side (the same applies to the fin portion 17 side), as shown in A of FIG. 7, the fin portion 16 is formed. The planned processing portions 38, 58, 18 of the holding portions 35, 55, which are overlapped with each other, are fixed by the movable presser mold 102 and the presser mold 104 of the holder 101 of the press mold 100, and then in B of FIG. As shown, the punch 103 through which the presser die 104 is inserted is applied to the planned machining portions 38, 58, 18 so as to be recessed, and the movable presser die 102 on the holder 101 side is further opened to push the punch 103 to the holder 101 side. The planned machining portions 38, 58, 18 are further pressed against the surface to be stretched by compression deformation, and an undercut portion (locking protrusion) 66 is formed at the plastic deformation portion 65a on the recessed side, and the undercut portion 66 is formed. Is processed to a size that locks it to the corresponding locking portion 67 of the plastic deformation portion 65b on the non-recessed side, and the scheduled machining portions 38, 58, 18 are processed by one press working using the press die 100. A total of 5 parts can be processed at the same time, and the airbag 10 and the inflator 25 can be easily assembled to the mounting base 30.

Therefore, in the airbag device 9 of the first embodiment, the airbag 10 and the inflator 25 can be easily assembled to the mounting base 30 while ensuring the gas sealability.

Then, in the first embodiment, the caulking joints 65 between the holding portions 35, 55 of the mounting base 30 and the bracket 50 and the holding portions 36, 56 are formed by plastic deformation processing by a lance lock.

In such a lance lock, as shown in B of FIG. 7, during machining, the sandwiching portions 35, 36, 55, 56 between the mounting base 30 and the bracket 50 and the fin portions 16, 17 of the airbag 10 are scheduled to be machined. Since a fracture surface (shear section) 68 as a constant cutting site is generated on both edges of 38, 58, and 18, wrinkles and the like near the planned processing portion 18 of the fin portions 16 and 17 are reduced, and the inflow port portion. The influence on 12 can be suppressed, and it is easy to secure good gas sealability. Incidentally, in the first embodiment, the fracture surfaces 68 and 68 on both edge sides of the plastic deformation portions 65a and 65b are axially orthogonal VDs orthogonal to the axial direction IDs of the cylindrical inflow port portion 12 of the airbag 10 and the inflator 25. The fracture surface 68 itself is arranged along the axial ID.

In the first embodiment, the holding portions 55 and 56 of the bracket 50 are divided into each scheduled processing portion 58 by leaving a space 57, but one sheet is used without leaving a space 57. As the plate-shaped sandwiching portions 55 and 56 of the above, a plurality of scheduled machining portions 58 for forming the caulking joint portion 65 may be arranged in each of the plate-shaped sandwiching portions 55 and 56. By the way, in such continuous single-piece sandwiching portions 55 and 56, when the sandwiching portions 35 and 36 of the single-sheet mounting base 30 which are not divided for each scheduled processing portion 38 are used, the airbag 10 In order to prevent the occurrence of wrinkles near each of the single fin portions 16 and 17, an opening is provided so that the fin portions 16 and 17 themselves are not interposed in the region of the caulking joint portion 65 in the fin portions 16 and 17. It may be provided. In this case, the opening peripheral edge is connected to the holding portions 55, 35 of the bracket 50 and the mounting base 30 and to each other of the holding portions 56, 36, so that the holding portions 55, 35 are in the vicinity of each other or the holding portion 56, Since the 36s are directly sandwiched in the vicinity of each other, wrinkles generated in the fin portions 16 and 17 can be suppressed, and the inflow port portion 12 can be connected to the inflator 25 with good sealing performance.

Further, in order to stabilize the joint state between the sandwiching portions 35, 55 and the sandwiching portions 36, 56, the airbag device 9A of the second embodiment shown in FIGS. 8 to 12 may be configured.

In this airbag device 9A, unlike the bracket 50 of the first embodiment, the bracket 50A made of sheet metal has two locking legs 60 formed on both sides of the half-split cylinder portion 53. The difference is that the holding portions 55A and 56A on which the scheduled processing portion 58 is arranged are arranged between the left and right locking leg portions 60 and 60.

The locking leg portion 60 has a holding portion 55A. Through holes 40, 20 provided in the holding portions 35A, 36A of the mounting base 30A and the fin portions 16A, 17A of the airbag 10A, projecting so as to be substantially orthogonal to the holding surfaces 55a, 56a on the mounting base 30A side of the 56A. The shaft portion 61 penetrating the shaft portion 61 and the tip of the shaft portion 61 are bent in a direction away from the half-split cylinder portion 53, and the back surfaces of the holding portions 35A and 36A of the mounting base 30A (the back surfaces of the holding surfaces 35a and 36a) 35b. , A locking claw 62 capable of locking the peripheral edge of the through hole 40 on the 36b side.

Further, the airbag 10A is different from the airbag 10 of the first embodiment in that through holes 20 are formed on both the left and right sides of the scheduled processing portions 18 of the fin portions 16A and 17A. Further, the mounting base 30A is also different from the mounting base 30 of the first embodiment in that through holes 40 are formed on both left and right sides of the scheduled processing portion 38 of the sandwiching portions 35A and 36A.

Both of these through holes 20 and 40 have a wide opening 21 and 41 through which the locking claw 62 of the locking leg 60 can be inserted, and a wide opening 21 in the direction along the axial ID of the half-split cylinder 53. , 41, and narrow openings 22 and 42 that allow the shaft portion 61 to be inserted and the locking claw 62 to be impassable.

In the second embodiment, after the inflator 25 is inserted into the inflow port portion 12 of the airbag 10A in which the main body portion 11 is folded, the inflow port portion 12 is housed in the half-split cylinder portion 33 of the mounting base 30A, and the fin portion is provided. When the 16A and 17A are placed on the holding surfaces 35a and 36a of the holding portions 35A and 36A of the mounting base 30A and the bracket 50A is put on, the locking claw 62 side of each locking leg 60 of the bracket 50A is subjected to the corresponding air. The fin portions 16A, 17A of the bag 10A and the holding portions 35A, 36A of the mounting base 30A are inserted into the wide openings 21, 41 of the through holes 20, 40, and the shaft portion 61 is inserted into the wide openings 21, 41. To the narrow openings 22 and 42, each locking claw 62 is locked to the peripheral edge of the narrow openings 22 and 42. Then, as in the first embodiment, the caulking joint portion 65 is formed by the lance lock, and the inflator 25 and the airbag 10A are assembled to the mounting base 30A while ensuring the gas sealability. That is, in this second embodiment, the caulking joint 65 moves each locking leg 60 of the bracket 50A from the wide openings 21, 41 of the through holes 20, 40 to the narrow openings 22, 42. It is configured to be formed in the arranged state.

In the airbag device 9A of the second embodiment, the same action and effect as those of the first embodiment can be obtained, and further, the following actions and effects can be obtained. That is, even if the holding portions 55A and 56A of the bracket 50A try to separate from the holding portions 35A and 36A of the mounting base 30A, the locking leg 60 of the bracket 50A holds the locking claw 62 and the holding portion 35A of the mounting base 30A. Since the back surfaces 35b and 36b sides of 36A are locked, even if the caulking joint portion 65 is loosened, the behavior is such that the holding portions 35A and 36A of the mounting base 30A in the holding portions 55A and 56A of the bracket 50A are peeled off. It can be accurately prevented, and the mounting base 30A can secure the gas sealability and stably hold the airbag 10A and the inflator 25.

When the caulking joint is formed by plastic deformation processing, tox caulking may be used in addition to the lance lock. As shown in A of FIG. 13, this tox caulking is performed, for example, on the fin portion 16 side of the airbag 10 (the same applies to the fin portion 17 side), the holding portions 35, 55 in which the fin portions 16 are overlapped. The planned machining portions 18, 38, 58 of the above are fixed by the movable presser die 102A and the presser die 104A on the holder 101A side of the press die 100A, and the punch 103A through which the presser die 104A is inserted is recessed. The overlapping sandwiching portions 35 and 55 are plastically deformed by applying them to 18, 38, 58, and further, the movable presser mold 102A on the holder 101A side is opened, and the punch 103A is further pressed against the holder 101A side to further press the planned processing portion. 38, 58 are compressed to form an undercut portion (locking protrusion) 66 at the plastic deformation portion 65a, and the undercut portion 66 is processed to a size that locks the undercut portion 66 with the corresponding locking portion 67 of the plastic deformation portion 65b. Then, the caulking joint portion 65A is formed. Therefore, the caulking joint portion 65A for joining the holding portions 35 and 55 can be easily formed by tox caulking using a predetermined press mold 100A.

Further, in each embodiment, the case where the mounting bases 30 and 30A are formed in a substantially flat plate shape is shown, but as a rectangular parallelepiped box shape, a half-split cylinder portion 33 and a holding portion 35, 36 are formed on a box-shaped bottom wall portion. May be formed so as to dispose of.

Further, in each embodiment, the knee protection airbag devices 9 and 9A for protecting the knees of the passenger seat occupant have been described, but an inflator is inserted into the inlet portion of the airbag and a bracket is used. As long as it is an airbag device to be assembled to the mounting base, the present invention is not limited to the knee protection airbag device, and the present invention may be applied to a passenger airbag device or the like that protects the upper body of a passenger in the passenger seat. good.

9,9A ... (for knee protection) Airbag device, 10,10A ... Airbag, 11 ... Main body, 12 ... Inlet, 16,16A, 17,17A ... (Inner edge side) Fin, 20 ... Through hole , 21 ... Wide opening, 22 ... Narrow opening, 25 ... Inflator, 27 ... Gas discharge, 30, 30A ... Mounting base, 31, 31A ... Holding plate, 33 ... Half-split cylinder, 35, 36, 35A, 36A ... Holding part, 40 ... Through hole, 41 ... Wide opening, 42 ... Narrow opening, 50, 50A ... Bracket, 53 ... Half-split cylinder part, 55, 56, 55A, 56A ... Holding part, 60 ... Locking leg, 61 ... Shaft, 62 ... Locking claw, 65, 65A ... Caulking joint, 66 ... (Locking protrusion) Undercut, VD ... Axis orthogonal direction, G ... Expansion gas.

Claims (3)

An airbag that expands by inflowing expansion gas,
An inflator that supplies expansion gas to the airbag and
A sheet metal mounting base that holds the airbag and the inflator and is mounted on the mounting site.
A sheet metal bracket that attaches the inflator to the mounting base,
It is an airbag device that is configured with
The inflator has a substantially cylindrical shape in which a gas discharge portion for discharging expansion gas is arranged on the tip side.
The airbag is formed of a flexible sheet material,
The main body that expands by inflowing expansion gas from the folded state,
It is provided with a cylindrical inflow port portion that communicates with the main body portion, inserts the tip end side of the inflator, and allows expansion gas from the inflator to flow into the main body portion.
It is configured to include fins protruding on both sides of the inflow port in the direction orthogonal to the axis on the outer peripheral surface side of the inflow port.
The mounting base and the bracket
Approximately half the circumference of the outer circumference of the air bag into which the inflator is inserted can be wrapped around the outer circumference of the substantially cylindrical inflow port portion, and approximately half the circumference of the outer circumference of the inflow port portion can be covered. Half-split cylinder and
A plate-shaped holding portion capable of mutually holding the fin portions on both sides of the inlet portion of the airbag, and a plate-shaped holding portion.
With
In a state where the sandwiching portion between the mounting base and the bracket sandwiches the fin portions on both sides of the inflow port portion, the fin portions are overlapped and integrally formed with each other, and mutual separation is regulated. An airbag device characterized in that it is connected to each other by a caulking joint formed by plastic deformation processing to form an undercut portion. The airbag device according to claim 1, wherein a caulking joint between the holding portion of the mounting base and the bracket is formed by plastic deformation processing by a lance lock. Locking legs are formed on both sides of the half-split cylinder portion of the bracket.
The locking legs are, respectively.
Penetration provided in the holding portion of the mounting base and the fin portion of the airbag so as to project from both side portions of the half-split cylinder portion so as to be substantially orthogonal to the holding surface of the holding portion of the bracket. The shaft that penetrates the hole and
A locking claw that can be bent from the tip of the shaft portion in a direction away from the half-split cylinder portion of the bracket to lock the peripheral edge of the through hole on the back surface side of the holding portion of the mounting base.
Is configured with
The through hole between the holding portion of the mounting base and the fin portion of the airbag has a wide opening through which the locking claw can be inserted and the wide opening in a direction along the axial direction of the half-split cylinder portion. It is configured to include a narrow opening that is connected to the portion, allows the shaft portion to be inserted, and prevents the locking claw from being inserted.
1. The caulking joint is formed in a state in which the locking leg portion of the bracket is moved from the wide opening of the through hole to the narrow opening of the through hole. Alternatively, the airbag device according to claim 2.

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