JP2000296746A - Air bag folded form holding structure of air bag device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a band-shaped holding member for holding an air bag folded form, at high yielding, from an original material of an air bag and allow the holding member to be broken easily when the air bag is operated. SOLUTION: This holding structure is formed so that a band-shaped holding member 44 is applied to an air bag 12 disposed on a base plate in the state of being folded and its folded form is held. In this case, the holding member 44 is formed of those sheet materials cut out in fork shape, the tip end parts of both leg parts 48 cut off by this cut 46 are formed in band-shaped both end parts and locked to the base plate, and a connecting part 50 connecting both leg parts 48 to each other are broken by an internal pressure of the air bag 12 applied when an air bag device is operated so that the connecting part 12 is burst starting from a cut terminal 46a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a folded structure of an airbag in an airbag device.

[0002]

2. Description of the Related Art Generally, an airbag device as a device for protecting an occupant in a vehicle or the like includes a folded airbag, an inflator for supplying gas to the airbag, and a base plate to which the airbag and the inflator are attached and fixed. The airbag device includes a bag receiving member, such as an airbag, a case, and the like, and a cover that is disposed so as to cover the upper surface of the folded airbag and that is opened by the internal pressure of the airbag when the airbag device operates.

[0003] In such an airbag device, the workability in mounting the cover is improved, and the deformation of the cover due to a spontaneous restoring force from the folded state of the airbag when mounted on a vehicle is prevented. For this purpose, the folded shape of the airbag is maintained by hanging the band-shaped member on the airbag or covering the case opening with a lid-shaped member. These folding-shaped holding members are ruptured by the internal pressure of the airbag when the airbag device is operated, and a fragile portion such as a perforation is provided at the rupture portion, and the rupture starts from the fragile portion. It is devised as follows.

For example, a conventional airbag apparatus 100 shown in FIG. 8 has a folded airbag 101, a disc-shaped inflator 102, and a rectangular plate-shaped base plate to which the airbag 101 and the inflator 102 are attached and fixed. 103 and the airbag 101 with the base plate 1
03 and the airbag 1
01 and the airbag 101
A holding member 106 made of a band-shaped cloth is hung around the airbag 101 to hold the folded shape of the airbag 101. The holding member 106 is provided with a weak portion 107 formed of a perforation at a central portion in the longitudinal direction, and the holding member 106 exerts a pulling force applied by the internal pressure of the airbag 101 when the airbag device 100 operates. Thus, the fragile portion 107 is broken.

An airbag is usually manufactured by cutting a panel of a predetermined shape from a long raw material and sewing the panel. At this time, it is economical to cut the holding member by using the remaining raw material remaining after cutting the panel.

For example, when manufacturing a circular airbag such as an airbag for a driver's seat, as shown in FIG. The circular panel 121 is cut at a predetermined interval, and the band-shaped holding member 106 is cut at the remaining portion of the raw material sandwiched between the circular panels 121.

[0007]

In order to efficiently cut the panel 121 constituting the airbag from the long fabric cloth 120 as described above, it is effective to make the cutting interval of the panel 121 as narrow as possible. However, if the cutting interval is too small, the area of the remaining web remaining after cutting becomes small, and it becomes difficult to obtain the holding member 106. For example, as shown in FIG. 9B, when the cutting interval a of the panel 121 is smaller than the width b of the holding member 106, when the holding member 106 is to be cut at the remaining raw material, the holding member 10 is cut.
As a result, the holding member 106 cannot be cut off. This depends on the length of the holding member 106, but the length of the holding member 106 cannot be easily changed because it is determined by the shape and the folding method of the airbag. In the case of obtaining the holding member, there is a problem that the yield is low due to the restriction of the cutting interval of the panel constituting the airbag.

Further, since the conventional holding member 106 breaks the fragile portion 107 such as a perforation by a tensile force due to the internal pressure of the airbag 101, a relatively high strength is required to provide the fragile portion 107. Technology is needed.

Therefore, the present invention provides an airbag which can obtain a panel and a holding member constituting an airbag with good yield from a raw material and can easily break the holding member when the airbag device is operated. It is an object of the present invention to provide a folded holding structure.

[0010]

SUMMARY OF THE INVENTION A folded structure of an airbag in an airbag apparatus according to the present invention comprises an airbag having a folded airbag and a bag receiving member to which the airbag is attached and fixed. The apparatus has a structure in which a band-shaped holding member is hung on the folded airbag to hold the folded shape, and the holding member is formed of a sheet-like material cut in a forked shape. The ends of the separated two legs are the two ends of the band and are locked to the bag receiving member, and the connecting portion of the holding member connecting the two legs is air-tight when the airbag device is operated. The internal pressure of the bag breaks at the end of the cut.

According to this holding structure, when the internal pressure of the airbag acts on the holding member during operation of the airbag device,
The holding member breaks from the end of the cut so that the connecting portion is torn. In general, since a sheet-like material has a smaller tearing force than a tensile force, by breaking the holding member with the tearing force in this manner, a weak portion such as a perforation required when the holding member is broken by the tensile force. Need not be provided. Further, since the holding member is made of a sheet-like material cut in a forked shape, the length of the band-like holding member suspended from the airbag is about twice the original length of the sheet-like material. That is, the cutting length when cutting the holding member from the raw material can be about half the length of the holding member to be obtained. Therefore, when cutting the panel constituting the airbag from the raw material and obtaining the holding member with the remaining portion, the restriction on the cutting interval of the panel is reduced, and therefore, it is possible to improve the yield by narrowing the cutting interval. it can.

In the holding structure, the bag receiving member is a plate-shaped base plate to which a mouth portion of the airbag is attached and fixed, and the holding member is folded on the base plate and supported on the base plate. May be hung around an airbag.

[0013] In the holding structure, the bag receiving member is a case having an opening for accommodating the airbag and inflating the airbag, and the holding member is provided with an opening of the case. It may be hung on the folded airbag by being fixed to the side of the case so as to bridge the part.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view of an airbag device 10 according to one embodiment of the present invention, and FIG.
FIG. 3 is a sectional view of the airbag 12 according to the first embodiment.
FIG. 4 is a perspective view of the holding member 44 in the same embodiment, and FIG.
It is a perspective view which shows the state hold | maintained at 4.

The airbag device 10 is a driver's seat airbag device disposed at the center of the steering wheel of an automobile. The airbag device 12 includes an airbag 12 and an inflator 14.
, A base plate 16, a bag retainer 18, and a cover 20.

The airbag 12 is formed in a bag shape by sewing the peripheral edges of two substantially circular panels 22a and 22b together, and the panel 22b disposed on the inflator 14 side has a central portion. A mouth portion 24 for receiving gas supply from the inflator 14 is provided, and a vent hole 26 is provided on a peripheral portion. These panels 22 are obtained by cutting a long raw cloth 70 into a circular shape at predetermined intervals, as shown in FIG.

The inflator 14 has a disc-like shape and is provided with a mounting flange 14a.
The upper part is the gas blowing part 14b.

The base plate 16 is a metal bag receiving member to which the airbag 12 and the inflator 14 are attached and fixed. The base plate 16 has a substantially rectangular plate-shaped portion 30 for receiving the lower surface of the folded airbag 12, The side portion 32 is formed by bending downward from the periphery of the portion 30.

An opening 34 is provided at the center of the plate-like portion 30 of the base plate 16, and as shown in FIG.
The gas blowing portion 14b of the inflator 14 is inserted into and fixed to the opening 34 from the back side. And the opening 3
The opening 34 is provided with a mouth 24 of the airbag 12 at the peripheral edge of the opening 34 so as to receive the gas blowing portion 14b of the inflator 14 projecting toward the surface of the base plate 16 through the surface 4 from the front side. It is mounted and fixed via a bag retainer 18. More specifically, the bag retainer 18 is a metal member having an opening 36 provided at the center of a substantially rectangular plate-like member and bolts 38 protruding at four corners. Into the through hole 28 provided in the vicinity of the mouth portion 24, and further, through the opening 3 of the base plate 16.
4 and a through hole 35 provided in the flange 14 a of the inflator 14 and penetrated through the through hole 35.

The cover 20 is provided with the folded airbag 12.
A door portion 40 that covers the upper surface of the airbag device and is pushed open by the internal pressure of the airbag 12 when the airbag device 10 is activated,
Is a synthetic resin member comprising a wall portion 42 that protrudes from the back surface of the airbag 12 and surrounds the side surface of the folded airbag 12 over the entire circumference. The cover 20 is attached to the base plate 16 by fixing the wall 42 to the side surface 32 of the base plate 16 with rivets 43, and forms a storage space for the airbag 12 together with the base plate 16.

Reference numeral 44 denotes a band-shaped holding member which is hung on the airbag 12 folded in a predetermined shape and holds the folded shape. The holding member 44 is hung on the opposite side surface and the upper surface of the folded airbag 12, that is, the surface that is not supported by the base plate 16, and holds the folded shape.

As shown in FIG. 4A, the holding member 44 is made of a sheet-like material 45 cut in a forked shape. The sheet-like material 45 has a rectangular shape, and is provided with a notch 46 extending in the longitudinal direction at the center in the width direction.
6 is formed so as to reach the short side on one side opposed to the longitudinal direction of the sheet-like material 45, but not to the short side on the other side, whereby the two legs are bifurcated. A connecting portion 50 for connecting the portion 48 and both leg portions 48 is formed. Through holes 52 through which the bolts 38 of the bag retainer 18 penetrate are provided at the distal end portions (free ends) of the both leg portions 48, respectively.

As shown in FIG. 3, the sheet-like material 45 is sandwiched between the two panels 22 at a remaining portion of the remaining raw fabric obtained by cutting the panel 22 constituting the airbag 12 from the long raw fabric 70. It is obtained by cutting the ear part of the bent part into a rectangular shape. The sheet-like material 45 has a longitudinal direction directed in the width direction of the raw cloth 70, and one short side thereof is
The raw cloth 7 is cut so as to coincide with the width direction end of the cloth 7.
A notch 46 is formed from the end in the width direction of zero.

As shown in FIG.
Is formed in an elongated strip shape by holding the tip of one leg 48 upside down and pulling the two legs 48 apart in the opposite direction, and the tips of the two legs 48 are formed in a strip shape. At both ends. Then, as shown in FIG. 4C, the band-shaped holding member 44 is attached to the base plate 1.
6 wraps around the folded airbag 12 supported on it. Specifically, as shown in FIGS. 5A and 5B, the bolt 38 of one of the bag retainers 18 is passed through a through hole 52 provided at the tip of one leg 48, and the holding member 44 is moved. After hanging on the folded airbag 12, the other leg 48 is turned upside down, and the bolt 38 which is diagonally opposite to the above-mentioned one bolt 38 is passed through the through hole 52 at the tip thereof. In this state, it is fixed to the base plate 16.

As a result, both ends of the holding member 44 are locked to the base plate 16 and the holding member 44 is hung on the airbag 12 so that the central connecting portion 50 is located on the upper surface of the airbag 12. Specifically, as shown in FIG.
The holding member 44 runs in the width direction center of the surface of the airbag 12 where the cut side by the cut 46 is folded, and one leg 48 and the other leg 48 are connected in a stepped manner via a connecting portion 50. As shown in FIG.

In the airbag apparatus 10, when the cover 20 is mounted on the base plate 16 so as to cover the airbag 12 during the assembling operation, the folded shape of the airbag 12 is maintained by the holding member 44. , It is easy to put the cover 20 on the airbag 12,
Therefore, the workability of assembling the airbag device 10 is excellent. Further, even when mounted on a vehicle, the folded shape of the airbag 12 is held by the holding member 44, so that the force for automatically restoring the shape from the folded state acting on the cover 20 is reduced, The deformation of the cover 20 can be prevented.

When the gas generated by the inflator 14 increases the internal pressure of the airbag 12, the internal pressure acts on the holding member 44, so that the holding member 4
4 breaks such that the connecting portion 50 is torn from the terminal (end) 46a of the cut 46 as a starting point. As described above, by changing from the conventional breaking by the tensile force to the breaking by the tearing force, the holding member 44 can be easily broken without providing a broken portion such as a perforation, and the manufacturing is easy. . In particular, in the present embodiment, since the connecting portion 50 to be broken is located on the upper surface of the folded airbag 12, the inflation pressure of the airbag 12 is reduced by the connecting portion 5.
It effectively acts on the 0 cut terminal 46a.

Further, since the cutting length L when cutting the holding member 44 from the raw cloth 70 is only about half the length of the holding member 44 to be obtained, as shown in FIG. Cloth 70
When the panel 22 constituting the airbag 12 is cut from the above and the holding member 44 is cut with the remaining portion, the panel 22
The holding member 44 can be obtained even when the cutting interval A is made narrower so that the cutting interval A is smaller than the width B of the holding member 44, and the panel 22 and the holding member 44 are cut from the raw cloth 70. In this case, the yield can be improved, and the cost of the airbag 12 can be reduced.

In the above-described embodiment, the two legs 48 of the holding member 44 are engaged with the base plate 16 with the front and back inverted. However, the present invention is not limited to this. As shown in FIG. The legs 48 may be pulled apart in opposite directions so as to be locked to the base plate 16 on the same plane, and may be hung on the folded airbag 12. In this case, the holding member 44 is hung so that both legs 48 pass through the center of the folded airbag 12 in the width direction.

In the above embodiment, the base plate 1 is used as a bag receiving member for receiving the airbag 12.
6, the present invention employs a case 82 for storing an airbag 12 and an inflator (not shown) as shown in FIG.
The present invention can also be applied to an airbag device 80 that uses an airbag. In the example shown in FIG. 7, the airbag 12
Are stored in a folded state, and the mouth portion of the airbag 12 is fixed to the side surface of the case 82 with a plurality of rivets 84. Then, the holding member 44 is held so as to hold the folded shape of the airbag 12 housed in the case 82.
Is suspended on the upper surface of the airbag 12. More specifically, the distal ends of the legs 48 are fixed to the side surfaces of the case 82 by the rivets 84 so that the holding member 44 bridges the opening 86 of the case 82. In this case, similarly to the above-described embodiment, the holding member 44 is broken by the tearing force, so that it is not necessary to provide a fragile portion such as a perforation.
Further, the cutting length when cutting from the raw cloth is only about half of the holding member 44 to be obtained, so that the yield is improved.

Although the holding member 44 is made of the same woven fabric as the airbag 12 in the above embodiment, another woven fabric may be used, and the holding member 44 is not limited to a woven fabric or the like. For example, a sheet-like material such as rubber, resin, or paper may be used.

[0033]

According to the present invention, the holding member for holding the folded shape of the airbag is broken not by a pulling force but by a tearing force that is broken by a smaller force. The holding member can be easily broken without providing the portion. Also, since the cutting length when cutting the holding member from the web is only about half the length of the holding member to be obtained, the panel constituting the airbag is cut from the web and held by the remaining portion. When you get a member,
The constraints on the cutting interval of the panel are reduced, thus
The yield can be improved by reducing the cutting interval, and the manufacturing cost of the airbag can be reduced.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an airbag device according to an embodiment of the present invention.

FIG. 2 is a sectional view of the airbag device.

FIG. 3 is a plan view of a fabric cloth of the airbag according to the embodiment.

FIG. 4 is a perspective view of a holding member according to the embodiment;
(A) is a state after cutting, (b) is a state where both legs are spread,
(C) shows a state of being wound around the airbag.

FIGS. 5A and 5B are views showing the airbag held by the holding member in the same embodiment, wherein FIG. 5A is a perspective view as viewed from an upper surface side, and FIG. 5B is a perspective view as viewed from a lower surface side.

FIG. 6 is a perspective view showing a folded holding structure of an airbag according to another embodiment.

FIG. 7 is a perspective view showing a folded holding structure of an airbag according to still another embodiment.

FIG. 8 is an exploded perspective view of a conventional airbag device.

FIGS. 9A and 9B are plan views of a fabric cloth of an airbag in a conventional airbag apparatus.

[Explanation of symbols]

 Reference Signs List 10 airbag device 12 airbag 16 base plate 26 mouth portion of airbag 44 holding member 45 sheet material 46 cut 46a cut terminal 48 leg 50 Connecting portion 80 Airbag device 82 Case 86 Opening

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Tetsuya Sado 1-17-18 Edobori, Nishi-ku, Osaka-shi, Osaka Toyo Tire & Rubber Co., Ltd. F-term (reference) 3D054 AA02 AA13 BB05 CC50 FF16 FF17

Claims (3)

[Claims] 1. An airbag apparatus comprising a folded airbag and a bag receiving member to which the airbag is attached and fixed, wherein the folded shape of the airbag is obtained by suspending a band-shaped holding member on the folded airbag. The holding member is made of a sheet-like material cut in a forked shape, and the front ends of both legs separated by the cut are formed as the both ends of the band shape, so that the bag receiving member is formed. The connection portion of the holding member that connects the two leg portions is locked to a member, and the connection portion of the holding member that connects the two leg portions is broken from the end of the cut by the internal pressure of the airbag when the airbag device is activated. Folding holding structure. 2. The airbag according to claim 1, wherein the bag receiving member is a plate-shaped base plate to which a mouth portion of the airbag is attached and fixed, and the holding member is connected to the folded airbag supported on the base plate. The folded holding structure for an airbag according to claim 1, wherein the holding structure is wound around the airbag. 3. A case in which the bag receiving member has an opening for accommodating the airbag and inflating the airbag, wherein the holding member bridges the opening of the case. The folded airbag holding structure according to claim 1, wherein the airbag is suspended on the folded airbag by being fixed to a side surface of the case.