JPH0367749A - Air bag in air bag device - Google Patents

Abstract

PURPOSE:To surely restrain the inner pressure rising in an air bag after expansion of the bag is completed by constituting the air bag of a main chamber and auxiliary chambers each of which is separated from the main chamber by a bulkhead, and separating the bulkhead from an upper wall by means of a connecting member when the inner pressure of the main chamber is raised, thus expanding the auxiliary chambers. CONSTITUTION:This air bag 1 has a center main chamber 11 and two auxiliary chambers 12 arranged on the right and left sides of the main chamber 11, within a bag ground fabric 2 provided with a circular gas inlet opening 4 at the center of its lower part, the main chamber 11 and the auxiliary chambers 12 being separated from each other by two bulkheads 7 each connecting the periphery of the gas inlet opening 4 and the upper wall 3 of the bag ground fabric 2 together roughly in their vertical direction. Each bulkhead 7 is firmly sewed on the side of the periphery of the gas inlet opening 4 and is connected to the upper wall 3 by a sewing thread 8 which serves as a connecting member to be cut when the inner pressure of the main chamber 11 is raised. A few of position regulating straps 6, each of which is to be firmly sewed on the periphery of the gas inlet opening 4 and on the upper wall 3 to regulate the length of the main chamber 11 in its vertical direction during expansion of the air bag 1, are arranged within the main chamber 11.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an airbag of an airbag device installed in a vehicle. Specifically, the lower gas inlet periphery is attached to a mounting member, and A main chamber in which a gas inlet is arranged and an auxiliary chamber are separated by a partition wall arranged in the direction, and when gas flows in from the gas inlet,
The present invention relates to an airbag that is expanded from a folded state and is capable of suppressing the increase in internal pressure by inflating an auxiliary chamber when the internal pressure of the main chamber increases after the expansion.

<Conventional technology and its issues> Conventionally, airbags have been equipped with a main chamber and an auxiliary chamber, and when the internal pressure of the main chamber increases after expansion, gas flows into the auxiliary chamber to suppress the increase in the internal pressure of the main chamber. , the one described in Japanese Utility Model Publication No. 50-21246 is known.

In the airbag described in this publication, a main chamber with a gas inlet located at the bottom and an auxiliary chamber are provided with a partition wall arranged approximately vertically in between, and a through hole is formed in the partition wall. was.

In this airbag, when gas flows in from the gas inlet, it expands from the folded state, and when the internal pressure in the main chamber increases, the gas flows into the auxiliary chamber through the through hole in the partition wall. , which suppressed the increase in internal pressure in the main chamber.

However, this airbag has a through hole that is always open in a part of the partition wall, and gas flows into the auxiliary chamber through the through hole to inflate the auxiliary chamber before the airbag finishes expanding. Therefore, there is a risk that the auxiliary chamber will completely expand before the internal pressure of the main chamber increases, making it impossible to suppress the increase in the internal pressure of the main chamber.

This invention solves the above-mentioned problems, and the main chamber expands into a predetermined shape without the auxiliary chamber expanding during expansion, and when the internal pressure of the main chamber increases after expansion, the auxiliary chamber expands and expands. It is an object of the present invention to provide an airbag of an airbag device that can reliably suppress an increase in internal pressure after termination.

Means for Solving the Problems> The airbag of the airbag device according to the present invention has a lower gas inlet periphery attached to a mounting member, and
A main chamber in which the gas inlet is arranged and an auxiliary chamber are separated by a partition wall arranged in a substantially vertical direction, and when gas is inflowed from the gas inlet, the main chamber is expanded from the folded state. When the internal pressure of the main chamber increases after being opened and expanded,
An airbag of an airbag device capable of suppressing an increase in internal pressure by inflating the auxiliary chamber, wherein the main chamber has an exhaust hole formed around the gas inlet, and an exhaust hole formed between the gas inlet periphery and the upper side. A connecting member is provided with a position regulating strap that is connected to a wall to regulate the length of the main chamber in the vertical direction, and that allows the partition wall to be separated from the upper wall when the internal pressure of the main chamber increases. It is characterized in that it is connected to the upper wall with a .

<Operations and Effects of the Invention> In the air flap of the airbag device according to the present invention, when gas flows into the main chamber from the gas inflow port, the main chamber expands from the folded state.

At this time, the main chamber has an exhaust hole formed around the gas inlet, and a position regulating strap that is connected to the gas inlet periphery and the upper wall to regulate the length of the main chamber in the vertical direction. It is set up.

Therefore, excess gas that causes an increase in internal pressure in the main chamber that would separate the partition wall from the upper wall is discharged from the exhaust hole, while the position regulating strap restricts the length of the main chamber in the vertical direction. It becomes possible to expand into a predetermined shape. Further, a connecting member that allows the partition wall to be separated from the upper wall is connected to the upper wall side of the airbag remote from the gas inlet,
It is hardly affected by the gas flowing in from the gas inlet, and the risk of separating the partition wall from the upper wall during expansion of the main chamber is further reduced.

After the main chamber has expanded to a predetermined shape, the upper wall is recessed and the internal pressure of the main chamber increases, which cannot be dealt with simply by discharging gas from the exhaust hole, and a tensile force is applied to the partition wall. When the connecting member is cut or stretched, the partition wall is separated from the upper wall, and gas flows into the auxiliary chamber through the gap between the partition wall and the upper wall, causing the auxiliary chamber to expand and lowering the internal pressure of the main chamber. increase can be suppressed.

Therefore, in the airbag of the airbag device according to the present invention, the main chamber expands into a predetermined shape without inflating the auxiliary chamber at the time of expansion, and when the internal pressure of the main chamber increases after the expansion is completed, the auxiliary chamber expands and expands. It is possible to reliably suppress the increase in internal pressure in the main chamber after the opening is completed.

<Example> Hereinafter, one embodiment of the present invention will be described based on the drawings.

The airbag 1 of the embodiment shown in FIGS. 1 to 3 is constructed by disposing a partition wall 7, a position regulating strap 6, etc. inside a bag base fabric 2 having a circular gas inlet 4 at the center of the lower part. .

The bag base fabric 2 is made of a woven fabric such as nylon or polyester, and is coated with heat-resistant rubber on the inner circumference side, and is formed into a substantially spherical shape when fully inflated. ing.

Inside the bag base fabric 2 are two partition walls 7 that connect the periphery of the gas inlet 4 and the upper wall 3 of the bag base fabric 2 in a substantially vertical direction.
The main chamber 11 is separated into a central main chamber 11 and two auxiliary chambers 12 disposed on the left and right sides of the main chamber 11. The volume when the two auxiliary chambers 12 are inflated is the same as that of the main chamber 11.
The volume is approximately 5% or more of the expanded volume.

Each partition wall 7 is made of the same material as the bag base fabric 2, is firmly sewn to the peripheral edge of the gas canal inlet 4, and is sewn to the upper wall 3 as a disconnectable connecting member. They are connected using sewing thread 8.

In addition, inside the main chamber 11, the gas inlet 4 is firmly sewn to the periphery and the upper wall 3, and when gas is allowed to flow in from the gas inlet 4, the length of the main chamber 11 in the vertical direction is restricted. Four position regulating straps 6 are provided.

Furthermore, two exhaust holes 5 passing through the bag base fabric 2 are formed around the periphery of the gas inlet 4 in the main chamber 11 . The opening area and number of these exhaust holes 5 are set in relation to the strength of the sewing thread 8. When gas flows into the main chamber 11 through the gas inlet 4, the main chamber 11 During the expansion, the internal pressure of the main chamber 11 increases to prevent the sewing thread 8 from being cut, so that excess gas can be discharged.

The airbag 1 is in a folded state in which the upper wall 3 of the bag base fabric 2 approaches the gas inlet 4 and the outer peripheral edge side of the bag base fabric 2 is folded upward. To explain how to fold the airbag 1, first fold the airbag 1 horizontally as shown in Fig. 5 from the expanded circular shape seen from above, then vertically as shown in Fig. 6. Fold and fold.

The periphery of the gas inlet 4 of the bag base fabric 2 is attached to the bag holder (attachment) using a nut 25 and a bolt 22 that is fixed to the annular retainer 21 and passes through the periphery of the gas inlet 4 of the bag base fabric 2. member) 26.

This bag holder 26 is attached with a flange portion 24 of an inflator 23 that allows a predetermined gas to flow into the airbag 1 from the gas inlet 4 at a predetermined time using bolts 22 and nuts 25.

The bag holder 26 also holds a pad (not shown) that covers the periphery of the airbag 1 in a folded state, and holds an airbag device M consisting of a pad/airbag inflator 23 (not shown) and the bag holder 26 in a predetermined position. It serves to attach to a steering wheel (not shown) or the like.

Furthermore, regarding the assembly of the airbag device M,
A bolt 22 is passed through the periphery of the gas inlet 4 in the airbag 1 and a retainer 21 is disposed, and the airbag 1 is closed in this state.
After that, the air bag inflator 23 and a pad (not shown) are sequentially assembled to the bag holder 26.

The operation mode of the airbag 1 of this embodiment will be described.

When gas flows into the main chamber 11 from the gas inlet 4, the main chamber 1 expands from the folded state.

At that time, a sewing thread 8 is attached to the periphery of the gas inlet 4 in the main chamber 11.
Exhaust holes 5 having a predetermined opening area and number set in relation to the strength of the main chamber 11 are formed, and are firmly connected to the periphery of the gas inlet 4 and the upper wall 3 to extend the length of the main chamber 11 in the vertical direction. A position regulating strap 6 is provided to regulate the position.

Therefore, in order to prevent the internal pressure of the main chamber 11 from rising during the expansion of the main chamber 11 and cutting the sewing thread 8, the surplus gas is exhausted from the exhaust holes 5 and 5, and the position regulating strap 6 The length of the main chamber 11 in the vertical direction is regulated, and the main chamber 11 expands into a predetermined shape.

In addition, at that time, a cuttable sewing thread 8 that allows the partition wall 7 to be separated from the upper wall 3 is connected to the upper wall 3 side of the airbag 1 that is away from the gas inlet 4. Since the main chamber 11 is less susceptible to the influence of gas flowing in from the main chamber 11, the risk of separation of the partition wall 7 from the upper wall 3 during expansion of the main chamber 11 is further reduced.

After the main chamber 11 has expanded into a predetermined shape, the upper wall 3 is recessed, as shown in FIG. When the internal pressure increases, a tensile force acts on each partition wall 7,
The suture thread 8 is cut to separate the septum 7 from the top wall 3;
Then, gas flows into the auxiliary chamber 12 through the gap between the partition wall 7 and the upper wall 3, the auxiliary chamber 12 expands, and an increase in the internal pressure of the main chamber 11 can be suppressed. The effect is similar to that described in the column.

In the embodiment, two auxiliary chambers 12 are provided, but the number of auxiliary chambers 12 may be one or three or more, and the arrangement shape of the auxiliary chambers 12 may also be changed, for example, by the partition wall 7. They can be arranged in various shapes, such as being arranged in a cylindrical shape around the gas inlet 4 or in an annular shape.

Further, in the embodiment, the separable sewing thread 8 is used as a connecting member to the upper wall 3 of the partition wall 7, but a separable adhesive may be used as the connecting member. 6
- As shown in Figure 7, multiple pieces of stretchable tape material 18
may be used as connecting members to be adhered to the partition wall 7 and the upper wall 3, respectively.Furthermore, the sewing thread 8 may be made of elastic material.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing the state when the airbag in one embodiment of the present invention has finished being expanded; FIG. 2 is a cross-sectional view showing the state when the auxiliary chamber of the same embodiment is inflated; The figure is a plan view showing the state when the auxiliary chamber of the same embodiment is inflated, Figure 4 is a plan view and side view showing the horizontal folding of the same embodiment, and Figure 5 is the vertical folding of the same embodiment. FIG. 6 is a cross-sectional view showing the state of another embodiment when the expansion is completed; FIG. 7 is a cross-sectional view showing the state of the same embodiment when the auxiliary chamber is inflated. It is. DESCRIPTION OF SYMBOLS 1... Airbag, 2... Bag base fabric, 3... Upper wall, 4... Gas inlet, 5... Exhaust hole, 6... Position regulating strap, 7... Partition wall , 8... Sewing thread, 11... Main chamber, 12... Auxiliary chamber, 26... (Mounting member) Bag holder. M...Airbag device. Figure 1 Patent Applicant Figure 2 Figure Figure Figure Figure Figure

Claims (1)

[Scope of Claims] A main chamber in which the lower gas inlet periphery is attached to a mounting member, and a partition wall disposed in a substantially vertical direction, in which the gas inlet is arranged, and an auxiliary chamber. When the gas is inflowed from the gas inlet, the main chamber is expanded from the folded state, and when the internal pressure of the main chamber increases after the expansion,
The airbag of the airbag device is capable of inflating the auxiliary chamber and suppressing a rise in internal pressure, wherein the main chamber has an exhaust hole formed around the gas inlet, and an exhaust hole formed between the gas inlet periphery and the upper side. A connecting member is provided with a position regulating strap that is connected to a wall to regulate the length of the main chamber in the vertical direction, and that allows the partition wall to be separated from the upper wall when the internal pressure of the main chamber increases. An airbag of an airbag device, characterized in that the airbag is connected to the upper wall with a.