Cushion structure of side airbag

The invention provides a cushion structure of a side airbag that includes: an inflator generating inflation gas in response to an inflation signal that is inputted in a collision; and a cushion inflated by the inflation gas supplied from the inflator. The cushion is divided into an upper cushion and a lower cushion by an intermediate diaphragm. The upper cushion and the lower cushion are fluidly communicated with each other through the intermediate diaphragm having at least a communication hole, and receive the inflation gas from the inflator. The upper cushion inflates in larger width than the lower cushion.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is based on, and claims priority from, Korean Application Serial Number 10-2007-0130013, filed on Dec. 13, 2007, the disclosure of which is hereby incorporated by reference herein in its entirety.

FIELD OF THE INVENTION

The present invention relates to a cushion structure of a side airbag, particularly a cushion structure of a side airbag that can reduce damage to a passenger by making the volume of an upper cushion larger than that of a lower cushion inside a cushion that inflates in a collision.

BACKGROUND OF THE INVENTION

In general, a side airbag is mounted inside a vehicle to secure protection for the passenger's chest and pelvis in a collision.

For the protection, the side airbag includes an inflator that generates high-pressure inflation gas by burning a gas generating agent in response to an inflation signal inputted in a collision and a cushion that is inflated toward the side of a passenger by the inflation gas supplied from the inflator.

The above cushion is formed by sewing the edges of two fabrics such that sealed spaces are formed inside the fabrics and the upper and lower portions of the cushion have the same volume when inflation is finished, such that the upper portion of the cushion contacts the passenger's chest and the lower portion contacts the passenger's pelvis.

However, the chest of a human body is composed of the ribs that are structurally weak relative to the pelvis, such that when a side airbag with a cushion having the same shock-absorbing performance is used, the damage to a passenger caused by a collision is relatively larger at the chest than the pelvis.

Therefore, proper measures should be variously devised for the side airbag in design to minimize damage to the passenger's chest.

SUMMARY OF THE INVENTION

Embodiments of the present invention provide a cushion structure of an airbag that achieves an optimal shock-absorbing effect for the passenger's body when a cushion inflates, by making the volumes of the upper and lower cushions inside the cushion of the side airbag different and appropriately distributing inflation pressure throughout the inside of the cushion.

According to an embodiment of the invention, a cushion structure of a side airbag includes an inflator and a cushion. The inflator generates inflation gas in response to an inflation signal that is inputted in a collision and the cushion is inflated by the inflation gas supplied from the inflator. The cushion is divided into an upper cushion and a lower cushion by an intermediate diaphragm. The upper cushion and the lower cushion are fluidly communicated with each other through the intermediate diaphragm having at least a communication hole, and receive the inflation gas from the inflator. The upper cushion inflates in larger width than the lower cushion.

According to a cushion structure of a side airbag of the invention, it is possible to minimize damage to a passenger while appropriately distributing inflation pressure throughout the inside of the cushion of the airbag in a collision by dividing the cushion into an upper cushion having a large volume and a lower cushion having a smaller volume than the upper cushion and communicated with the upper cushion.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in the figures, a cushion structure of a side airbag includes an inflator10that generates high-pressure inflation gas by burning a gas generating agent in response to an inflation signal inputted in a collision and a cushion12that is inflated by the inflation gas supplied from inflator10.

Cushion12has an upper cushion12athat is inflated by the inflation gas supplied from inflator10to protect the passenger's chest, a lower cushion12bthat is inflated by the inflation gas supplied from inflation10to protect the passenger's pelvis, and an intermediate diaphragm12cthat divides the cushion12as upper cushion12aand lower cushion12band has at least a communicating hole12dthat fluidly communicates the upper cushion12awith the lower cushion12b. Therefore, it is possible to appropriately distribute the inflation pressure inside the cushion12by allowing the inflation gas to flow into the upper cushion12aand the lower cushion12bthrough the at least a communication hole12dformed through intermediate diaphragm12c.

In an exemplary embodiment of the present invention, the upper cushion12ais formed to have a height larger than the lower cushion12b.

The lower cushion12bis formed by sewing lower portions of two main fabrics A, B. The upper cushion12ais formed by sewing one sub-fabric C between two main fabrics A, B upwards from distal ends of the intermediate diaphragm12c. Further, the farther away the height of the upper cushion12ais from the intermediate diaphragm12c, the more the sub-fabric C disposed between upper portions of the main fabrics A, B gradually increases in width, and at least a vent hole20open to the outside is formed at the upper portion of sub-fabric C. In an embodiment of the present invention, the vent hole20is formed at a center of the upper portion of sub-fabric C.

To be more detailed, the upper cushion12ais formed of upper connecting portions22and24. The upper connecting portion22is made by connecting one edge of upper portion of the main fabric A with one edge of upper portion of the sub-fabric C. The upper connecting portion24is made by connecting the other edge of the upper portion of the sub-fabric C with one edge of upper portion of the main fabric B. The lower cushion12bis formed by connecting edge of lower portion of the main fabric A with edge of lower portion of the main fabric B.

Further, temporary connecting portions26,28are configured to couple the upper connecting portions22and24as explained hereinafter.

Referring toFIG. 3, in an exemplary embodiment of the present invention, the temporary connecting portions26and28are positioned on the upper connecting portions22and24and connected in a normal condition but separated in inflation of cushion12. The temporary connecting portions26and28are to be coupled. For example, the temporary connecting portions26and28can be sewed such that the upper connecting portions22and24can be separated when upper cushion12ais inflated by the inflation gas supplied from inflator10. In an exemplary embodiment of the present invention, the vent hole20formed at upper portion of the sub-fabric B is aligned in series with the temporary connecting portions26,28in vertical direction with respect to the longitudinal direction of the sub-fabric C. Accordingly, the temporary connecting portions26,28may be separated easily by the expanding force of the upper cushion12ainflated by the inflation gas supplied from inflator10.

Due to this configuration set forth above, the upper connecting portions22and24facilitate folding the upper cushion12aof cushion12into a small volume to put the side airbag into the side of a seat. Further, temporary connecting portions26,28temporarily prevents the inflation gas from being discharged through the vent hole20at the earlier inflation stage of cushion12, while they allow the inflation gas to be discharged through the vent hole20when the upper cushion12ahas completely inflated, pressing the passenger's chest, thereby absorbing the impact.

The inflator10has at least injection hole10ato supply the inflation gas into the upper cushion12aand an injection hole10bto supply the inflation gas into the lower cushion12b. Since the volume of the upper cushion12ais larger than that of the lower cushion12b, more injection holes are provided to the upper cushion12athan the lower cushion12bin an exemplary embodiment of the present invention. Therefore, as the inflator10supplies the high-pressure inflation gas into the cushion12through injection holes10aand10bin response to an inflation signal inputted in a side collision, the upper cushion12aand the lower cushion12binflate to protect the passenger's chest and pelvis, respectively.

Referring toFIG. 3, an upper length X of upper cushion12ain the width direction thereof is increased by the sub-fabric C disposed between main fabrics A, B of the upper cushion12aas the cushion12is inflated. That is, when the cushion12inflates, the lower cushion12bincreases as length Y in the width direction thereof but the upper length X of the upper cushion12ain the width direction thereof increases as much as summation of the width of sub-fabric C and the increased length Y of the lower cushion12b.

As a result, the volume of upper cushion12ais larger than that of lower cushion12b, such that it is possible to increase the shock-absorbing effect against the impact that is applied to the chest, i.e., the upper portion of the passenger's upper body when the cushion12inflates in a side collision. The shock-absorbing effect that is obtained by discharging the inflation gas through the vent hole20from the upper portion of sub-fabric C also contributes to the above shock absorbing effect, in addition to setting length X in the width direction of upper cushion12arelatively large.

Further, the volume of lower cushion12bis involved in absorbing the impact applied to the pelvis at the lower portion of the passenger's upper body.

That is, in cushion12of the side airbag that inflates in a side collision, since upper length X in the width direction of upper cushion12ais larger than length Y in the width direction of lower cushion12b, it is possible to minimize damage to the ribs of the chest having smaller strength than the pelvis in the passenger's body, thereby reducing injuries.

The forgoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiment were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. It is intended that technical spirit and scope of the present invention be defined by the Claims appended hereto and their equivalents.