JPH081150Y2 - Air bag equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an air bag device in which an inflator is communicated with a bag and the bag is inflated by the operation of the inflator when the vehicle is suddenly decelerated.

[Prior Art] In an air bag device, an inflator is communicated with the bag, and the bag is inflated by the operation of the inflator when the vehicle rapidly decelerates.

In this type of air bag device, an exhaust hole is formed in the bag, and when the vehicle is rapidly decelerated, the shape of the bag is deformed and the exhaust gas from the exhaust hole can absorb energy.

However, when the shape of the bag is deformed or the exhaust gas is exhausted from the exhaust hole, the amount of energy absorbed is substantially constant regardless of the degree of sudden deceleration of the vehicle.

[Problems to be solved by the device]

The present invention has been made in view of the above facts, and an object thereof is to obtain an air bag device that can effectively absorb energy according to the degree of rapid deceleration of the vehicle.

[Means for solving the problem]

The present invention is an air bag device in which an inflator is communicated with a bag and the bag is inflated by the operation of the inflator when the vehicle is suddenly decelerated. The air bag device is provided between the bag and the inflator. A bent portion formed on a member and deformed in a direction in which the bag expands when an internal pressure of a predetermined amount or more is applied when the bag expands, and an exhaust gas formed on the tubular member and opened by the deformation of the bent portion. And a hole.

[Action]

According to the present invention having the above-described configuration, when the degree of sudden deceleration of the vehicle is high at the time of sudden deceleration of the vehicle, that is, when the bag has a predetermined internal force, the pressure causes the bending portion of the tubular member to extend in the direction in which the bending portion extends. The deformation causes the exhaust hole to open, and the deformation of the bent portion and the exhaust from the exhaust hole reliably increase the amount of energy absorbed.

〔Example〕

1 to 4 show an air bag device 20 to which the present invention is applied.

In the air bag device 20, as shown in FIG. 4, a base plate 26 is supported by a hub 22A of the steering wheel 22 via a bracket 24 in a substantially parallel manner. An inflator 28 is attached to the base plate 26, and a tubular member 30 is attached so as to communicate with the inflator 28.

The inflator 28 penetrates substantially the center of the base plate 26, and the gas ejection port 32 is arranged inside the tubular member 30. A flange 34 is formed on the outer periphery of the inflator 28 so as to be joined to the surface of the base plate 26 on the side opposite to the occupant (the surface on the lower side of FIG. 4). Has been done. The inflator 28 is operated by a not-shown acceleration sensor when the vehicle is suddenly decelerated, and the gas is ejected from the gas ejection port 32 to the inside of the tubular member 30 by this operation.

The tubular member 30 has a cylindrical shape as shown in FIG. 3, and is arranged so that its axis extends along the axial direction of the steering wheel 22 (vertical direction in FIG. 4). The tubular member 30 is provided on the hub 22A side of the steering wheel 22 in the axial direction at one end (the fourth side).
The inner cylinder 30B and the outer cylinder 30C are integrally connected to each other at a joint portion 30A at one axial end on the lower side of the figure) to form a double cylinder shape. The inner cylinder 30B is formed with a flange 38 at one axial end opposite to the joint portion 30A, which is joined to the occupant side surface of the base plate 26 (upper surface in FIG. 4).
36 is inserted and fixed to the base plate 26 by the rivet 36 together with the inflator 28.

An open end of the bag 40 is attached to the tubular member 30 at the axial end portion (the axial end portion on the upper side in FIG. 4) of the outer cylinder 30C on the side opposite to the joint portion 30A and the base plate 26. A cover 42 for accommodating the bag 40 is attached therebetween.

The bag 40 is stored between the cover 42 and the base plate 26 in a folded state. In this bag 40, the outer cylinder 30C of the tubular member 30 is inserted inside through the opening, and in this inserted state, the rivet 44 is inserted into the edge portion on the opening side and is attached to the tubular member 30 by the rivet 44. There is. Therefore, the bag 40 is communicated with the inflator 28 through the tubular member 30, and when the vehicle is rapidly decelerated, gas is introduced through the tubular member 30 by the operation of the inflator 28 and is inflated by this gas.

A ring 45 is embedded around the cover 42, and the rivet 44 is inserted into the ring 45 and is attached to the tubular member 30 together with the bag 40 by the rivet 44. cover
In 42, a thin portion 46 is formed in a portion facing the base plate 26, and when the bag 40 is expanded during sudden deceleration of the vehicle, it is pressed by the bag 40 and fractures at the thin portion 46. As shown in FIGS. 1 and 2, the steering wheel 22 and the occupant are interposed.

In the air bag device 20 configured as described above, the amount of energy absorbed is increased when the degree of sudden deceleration of the vehicle is high during rapid deceleration of the vehicle.

The energy absorption structure will be described in detail below.
As shown in the figure, an exhaust hole 50 is formed in the bag 40, and when the vehicle is rapidly decelerated, the shape of the bag 40 is deformed and the exhaust gas from the exhaust hole 50 can absorb energy (see FIG. 1).

Further, the tubular member 30 has an inner cylinder as shown in FIG.
The axially intermediate portion of 30B is bent to form a bent portion 54 having a U-shaped cross section, and protrudes from the inner cylinder 30B at a substantially right angle outward in the radial direction. The bent portion 54 extends in the axial direction as shown in FIG. 2 when the degree of rapid deceleration of the vehicle during the rapid deceleration of the vehicle is high, that is, when the internal pressure acting on the bag 40 exceeds a predetermined range. It is designed to be deformed in the direction of. An exhaust hole 56 is formed at the folded portion of the bent portion 54. When the exhaust hole 56 has a low degree of sudden deceleration of the vehicle, that is, when the internal pressure acting on the bag 40 is within a predetermined range, the bent portions 54 are overlapped with each other as shown in FIG. Although the inside and outside of the tubular member 30 are sealed by the existence of the tubular member 30, when the internal pressure acting on the bag 40 exceeds a predetermined range such as when the vehicle is rapidly decelerated to a high degree, the bending portion 54 is expanded and deformed, as shown in FIG. As shown in FIG. 5, the inside of the tubular member 30 is communicated with the outside thereof by opening.

 Next, the operation of this embodiment will be described.

During rapid deceleration of the vehicle, the inflator 28 is actuated by an acceleration sensor (not shown), and this action causes gas to flow into the bag 40 through the tubular member 30, and the gas causes the bag 40 to expand. This expansion pressurizes the bag 40 to cover it.
The thin portion 46 of 42 is broken, and by this break, the bag 40 is interposed between the steering wheel 22 and the occupant, and the energy is absorbed by the shape deformation of the bag 40 and the exhaust from the exhaust hole 50 (see FIG. 1). .

Here, when the degree of rapid deceleration of the vehicle is high, that is, when the internal pressure acting on the bag 40 exceeds a predetermined range, the bending portion 54 is stretched and deformed by this pressure as shown in FIG. Due to the deformation of the bent portion 54, the exhaust hole 56
The energy is absorbed by the deformation of the shape of the bag 40 and the exhaust from the exhaust hole 50, as well as the deformation of the bent portion 54 and the exhaust from the exhaust hole 56.

Therefore, when the degree of rapid deceleration of the vehicle is high, the energy absorption amount is surely increased, whereby the energy can be effectively absorbed according to the degree of sudden deceleration of the vehicle.

The bent portion 54 may have a configuration in which the bag 40 is expanded and deformed by an internal pressure of a predetermined amount or more when the bag 40 is expanded during bag inflation, and is not limited to being formed in the inner cylinder 30B of the tubular member 30. Other structures such as the outer cylinder 30C may be used.

Further, the exhaust hole 56 may be configured so as to be opened by the extension deformation of the bent portion 54, and is not limited to being formed in the folded portion of the bent portion 54, but may be formed in the vicinity of the base portion of the bent portion 54 or the like. It may be a structure.

[Effect of device]

As described above, the air bag device according to the present invention has an excellent effect that energy can be effectively absorbed according to the degree of rapid deceleration of the vehicle.

[Brief description of drawings]

1 to 4 show an air bag device to which the present invention is applied, and FIG. 1 is a schematic cross-sectional view showing an operation in a normal case such as a low degree of sudden deceleration of a vehicle, corresponding to FIG. 2 and 3 are schematic cross-sectional views showing the operation when the degree of sudden deceleration of the vehicle is high, etc., and FIG. 3 is a perspective view of the tubular member of FIG. The figure is a schematic sectional view showing the overall structure. 20: Air bag device, 28: Inflator, 30: Cylindrical member, 40: Bag, 54: Bent portion, 56: Exhaust hole.

Claims (1)

[Scope of utility model registration request] 1. An air bag device in which an inflator communicates with the bag and the bag is inflated by the operation of the inflator when the vehicle is suddenly decelerated, the tubular member being provided between the bag and the inflator and connecting the two. A bent portion formed on the tubular member and deformed in a direction in which the bag is expanded by this pressure when an internal pressure of a predetermined amount or more is applied when the bag is expanded, and an opening formed by the deformation of the bent portion formed on the tubular member. An air bag device comprising: