JP5629127B2 - Airbag device - Google Patents

Description

  The present invention relates to an airbag apparatus in which a housing (diffuser) is installed around an inflator, among airbag apparatuses installed in an automobile, for example.

  For the purpose of ensuring the safety of passengers, some safety devices are installed in automobiles. An air bag device that inflates and deploys an air bag with high-pressure gas generated by operating an inflator in an emergency such as a collision is one of safety devices.

  In some airbag apparatuses, a housing is installed around the inflator to guide high-pressure gas radially injected from the outer peripheral surface of the inflator to the inside of the airbag when the inflator is activated.

  This housing is generally manufactured using a sturdy pipe having a thickness of several millimeters and a circular cross section (for example, Patent Document 1).

JP-A-11-1151

  The problem to be solved by the present invention is that, in the case of a conventional housing manufactured using a sturdy pipe, the weight of the housing becomes heavy, which is contrary to resource saving and weight reduction.

The present invention has been made to solve the above problems.
That is, in the present invention, the above-mentioned problem is solved by making the cross section of the housing elliptical and deforming the cross section of the housing into a circular shape when high pressure gas is injected from the inflator during operation of the inflator. is there.

That is, the airbag device of the present invention is
An inflator,
An airbag that is inflated and deployed by supplying a high-pressure gas radially injected from the outer peripheral surface of the inflator during operation of the inflator;
An airbag device including a housing that is disposed around an inflator and guides the radially injected high-pressure gas into the airbag,
The housing is
Cross section in the initial state mounted on the vehicle in an elliptical shape, upon actuation of the inflator, by the high-pressure gas injected radially from the inflator, the circumferential length of the housing cross-sectional shape is deformed into a substantially circular shape as it The most important feature is that the opening area of the cross section of the housing through which the high-pressure gas to be guided to the inside of the airbag flows can be increased .

  In the case of the same circumference, the circular area is larger by about 10 to 15% than the elliptical shape. Therefore, in the present invention, the housing housed in a compact manner has a cross section of an elliptical shape to a substantially circular shape so as to ensure a predetermined opening area larger than that when the inflator is activated by the injected high pressure gas. The plate thickness is made thin so that it can be deformed.

  Therefore, when the inflator is in operation, the cross-sectional area of the housing is increased and the high-pressure gas discharge efficiency is improved. In addition, since the opening area of the cross section of the housing is reduced when mounted on a vehicle, the size can be reduced. Furthermore, in order to make the cross-sectional shape deformable by this high-pressure gas, a metal plate having a plate thickness of less than 1 mm is generally used, so that the weight can be reduced.

  In the present invention, the configuration in which the cross-sectional shape of the housing can be deformed from an elliptical shape to a substantially circular shape by the high-pressure gas injected from the inflator is, for example, bending a metal plate, and connecting one end and the other end of the metal plate. What is necessary is just to make it overlap and make a cross section become elliptical shape.

  Moreover, what is necessary is just to perform the attachment of the housing to an inflator with the stud bolt attached to the inflator. At that time, if a long hole is provided in one of the opposite ends of the metal plate, a circular hole is provided in the other, and the circular hole is arranged on the inner peripheral side, and the stud bolt is passed through these holes, The oval shape can be easily retained and transformed into a circular shape.

  In the present invention, when the inflator is in operation, the cross-sectional shape of the housing is changed from an elliptical shape to a substantially circular shape by the high-pressure gas injected from the inflator and the cross-sectional area is increased, so that the high-pressure gas discharge efficiency is improved. In addition, when mounted on a vehicle, the height of the cross section and the opening area can be reduced, thereby enabling downsizing. Further, since a metal plate thinner than the conventional one is used so that the cross-sectional shape can be deformed, the weight can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic explaining the principal part of the airbag apparatus of this invention, (a) is the cross-sectional view which showed the state at the time of mounting to a vehicle, (b) is the cross-sectional view which showed the state after an inflator action | operation. is there. BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic explaining the housing which is a component of the airbag apparatus of this invention, (a) is a perspective view explaining a bending state, (b) is the expanded view before bending of the thin steel plate which forms a housing. It is a figure similar to FIG. 1 explaining the principal part of the other airbag apparatus of this invention.

  In the case of a rigid conventional pipe housing having a circular cross section, even when high pressure gas is injected from the inflator, the cross sectional shape of the housing itself hardly deforms. Therefore, in order to improve the discharge efficiency of the high-pressure gas, it is necessary to increase the diameter of the housing, a large height is required for the installation portion, and the weight of the housing also increases.

  The present invention has an elliptical cross section, and when the inflator is activated, the cross section is deformed into a substantially circular shape by the high-pressure gas injected from the inflator, thereby improving the discharge efficiency, reducing the size, and reducing the weight. Is.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic view for explaining a main part of the airbag apparatus of the present invention.

  Reference numeral 1 denotes a housing disposed around the inflator 2 in order to guide the high-pressure gas ejected from the inflator 2 to the inside of the airbag (not shown) when the inflator 2 is activated in an emergency such as a collision.

  In the present invention, the housing 1 has an elliptical cross section as shown in FIG. 1A in the initial state of being mounted on a vehicle. When the inflator 2 is activated and high-pressure gas is injected from the inflator 2, the cross-sectional shape of the housing 1 is deformed into a substantially circular shape as shown in FIG.

  Thus, when the inflator 2 is operated, the cross-sectional shape of the housing 1 is changed from an elliptical shape to a substantially circular shape, thereby increasing the cross-sectional area by about 10 to 15% and improving the high-pressure gas discharge efficiency. .

  By the way, although the structure which changes the cross-sectional shape of the housing 1 from an ellipse shape to a substantially circular shape at the time of the operation | movement of the inflator 2 is not ask | required in particular, What is necessary is just to be the following structures, for example.

  A rectangular cold-rolled steel sheet 1a having a thickness of 0.4 mm shown in FIG. 2 (a) is bent as shown in FIG. 2 (b), and both ends of one and the other as shown in FIG. 1 (a). Both ends are overlapped so that a through hole is formed by a circular hole 1ba and a long hole 1bb provided at substantially the same position of each part.

  Then, as shown in FIG. 1 (a), a stud bolt 2a attached to the inflator 2 is passed through the circular hole 1ba on the inner peripheral side and the long hole 1bb on the outer peripheral side that are overlapped so as to form a through hole. If it is fixed with the nut 3, the cross section of the housing 1 can be maintained in an elliptical shape.

  In such a configuration, when the inflator 2 is actuated to inject high-pressure gas and high pressure is applied to the inside of the housing 1, the steel plate 1a is deformed from an elliptical shape to a circular shape with the circumferential length unchanged. To do. Thereby, the opening area of a cross section increases by 10 to 15%.

  The present invention is not limited to the above examples, and the embodiments may be changed as appropriate as long as they fall within the scope of the technical idea described in each claim.

  That is, the airbag apparatus described above is a preferable example of the present invention, and other embodiments can be implemented or performed by various methods. In particular, the present invention is not limited to the detailed shape, size, configuration, and the like of the components shown in the accompanying drawings unless otherwise specified in the present specification. In addition, expressions and terms used in the present specification are for the purpose of explanation, and are not limited thereto unless specifically limited.

  For example, when the inflator 2 is actuated, the configuration in which the cross-sectional shape of the housing 1 is deformed from an elliptical shape to a substantially circular shape is not limited to the above example, and as shown in FIG. It is good also as a structure which formed the cold-rolled steel plate 1a bent in the shape of an ellipse. In this case, the mounting hole 1c of the housing 1 to the inflator 2 may not be the long hole 1bb. In the example of FIG. 3, when the inflator 2 is operated to inject high-pressure gas and high pressure is applied to the inside of the housing 1, the concavo-convex portion is stretched to form a substantially circular shape as shown in FIG. It becomes a cross-sectional shape.

  In addition, the above example shows a case in which the housing 1 is formed of a cold-rolled steel sheet 1a having a thickness of 0.4 mm. The high-pressure gas from the inflator 2 causes the cross-sectional shape from an elliptical shape to a substantially circular shape. The thickness is not limited to 0.4 mm.

  The optimum thickness may be determined mainly depending on the output of the inflator, but the preferred thickness is 0.3 mm to 1.0 mm. This is because if it is thinner than 0.3 mm, it deforms like paper due to the pressure of gas, and the circular cross section cannot be maintained. On the other hand, if the thickness exceeds 1.0 mm, the shape may not be sufficiently deformed from an elliptical shape to a circular shape.

  In addition, the metal plate to be used is not limited to a cold-rolled steel plate, and any metal plate such as a hot-rolled steel plate can be used as long as it can maintain an elliptical cross section and can be deformed from an elliptical shape to a substantially circular shape by high-pressure gas. May be used.

  The airbag device of the present invention is used by being installed in an automobile, but it can also be installed on a vehicle such as an aircraft or a ship other than a vehicle, and the same effect is exhibited.

DESCRIPTION OF SYMBOLS 1 Housing 1a Cold rolled steel plate 1ba Circular hole 1bb Long hole 2 Inflator 2a Stud bolt

Claims (5)

An inflator,
An airbag that is inflated and deployed by supplying a high-pressure gas radially injected from the outer peripheral surface of the inflator during operation of the inflator;
An airbag device including a housing that is disposed around an inflator and guides the radially injected high-pressure gas into the airbag,
The housing is
Cross section in the initial state mounted on the vehicle in an elliptical shape, upon actuation of the inflator, by the high-pressure gas injected radially from the inflator, the circumferential length of the housing cross-sectional shape is deformed into a substantially circular shape as it An airbag device characterized in that an opening area of a transverse section of the housing through which the high-pressure gas for guiding the inside of the airbag flows can be increased . The housing is
2. The airbag device according to claim 1, wherein the airbag device is formed by bending a metal plate and superimposing one end portion and the other end portion of the metal plate so that the cross section becomes an elliptical shape.   The airbag apparatus according to claim 1 or 2, wherein the housing is attached around the inflator by a stud bolt attached to the inflator.   4. A long hole is provided in one of both end portions where the metal plates overlap each other, and a circular hole is provided in the other, and the stud bolt passes through these holes to attach the metal plate. Airbag device.   The airbag device according to claim 4, wherein the metal plate is overlapped so that an end portion on the circular hole side of the metal plate is disposed on an inner peripheral side.

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