Active airbag venting system

An airbag assembly including an airbag inflatable from a housing in operation with an occupant classification system is provided in accordance with an exemplary embodiment of this disclosure. The occupant classification system is incorporated into a vehicle seat and is in communication with the airbag. A selectively actuatable vent formed in the airbag is opened during deployment of the airbag based on a determination from the occupant classification system.

FIELD

The present invention relates to an airbag for a passenger vehicle.

BACKGROUND

Many current passenger vehicles are equipped with airbags that deploy in certain vehicle impact events. Airbag deployment usually involves rapid inflation of the airbag with a gas. The inflation rate and force may be controlled in commercial passenger vehicle applications to meet various government regulations. As these regulations become more strict, however, the cost to produce airbag systems tends to increase due to the complexity of sensor systems that may be required to control inflation of the airbag, or disable inflation of the airbag.

SUMMARY

An airbag assembly is provided in accordance with an exemplary embodiment of this disclosure. The airbag assembly includes a housing, an inflatable airbag, a tether, and a selectively actuatable vent. The inflatable airbag is disposed within the housing. The selectively actuatable vent is formed on the airbag. The selectively actuatable vent is opened by the tether when the airbag deploys and the tether remains fixed to the housing. The selectively actuatable vent remains closed when the airbag deploys and the tether is detached from the housing.

An airbag assembly including an airbag inflatable from a housing in operation with an occupant classification system is provided in accordance with an exemplary embodiment of this disclosure. The occupant classification system is incorporated into a vehicle seat and is in communication with the airbag. A selectively actuatable vent formed in the airbag is opened during deployment of the airbag based on a command received from the occupant classification system.

Further areas of applicability of the present disclosure will become apparent from the detailed description, drawings and claims provided hereinafter. It should be understood that the detailed description, including disclosed embodiments and drawings, are merely exemplary in nature, intended for purposes of illustration only, and are not intended to limit the scope of the invention, its application, or use. Thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention.

DETAILED DESCRIPTION

FIGS. 1-3illustrate an air bag10according to the present disclosure. Airbag10may be used, for example, in a passenger vehicle. Although airbag10will be described below as a passenger-side airbag, the present disclosure should not be limited thereto. In this regard, airbag10may be used as a driver-side airbag, or as a side-curtain airbag. Regardless, as airbag10is deployed, airbag10is filled with a gas and expanded where airbag10may then be engaged with a passenger as is known in the art.

Airbag10includes a housing12that, as illustrated inFIGS. 1 and 2, may be integrated into a dashboard14of the vehicle. Alternatively, airbag10may be integrated into a steering wheel (not shown), a side-curtain (not shown), a pillar (not shown), or a door (not shown) of the vehicle. Housing12includes an inflator device16that, in the event of a collision, deploys a gas that rapidly inflates airbag10to protect a passenger in an impact event. Inflator device16may be any type of inflator device known to one skilled in the art.

Airbag10may be formed of conventional materials, in a conventional manner, and a conventional shape as is known in the art. In this regard, airbag10includes a front panel18, a pair of side panels20, and a rear panel22that define a wall24having an exterior26that may be engaged with a passenger, and an interior28that contains gas emitted by inflator device16in the event of deployment of airbag10. Side panels20are located on opposing sides of front panel18, while rear panel22is opposite to front panel18.

Airbag10can be in communication with, as shown schematically, an occupant classification system30. Occupant classification system30can be incorporated within a vehicle seat31of the motor vehicle, and can be used to detect information including, for example, a position of the seat31, a weight of the seat's occupant, and whether a seatbelt is in use. Occupant classification system30may also detect a tension on the seatbelt to determine whether a child seat is secured in the seat. Based on information detected by occupant classification system30, airbag10can be prevented from deploying (e.g., no occupant located in the seat) or ready to deploy (e.g., an occupant is present in the seat).

To detect a weight of the seat's occupant and a position of the seat31, occupant classification system30can include at least a pressure sensor32, a seat position sensor34, and an electronic control unit (ECU)36. When an occupant sits on the seat, pressure sensor32signals the occupant's weight to ECU36. ECU36then sends that information to airbag10, which also includes an ECU37. In contemplated exemplary embodiments, the occupant classification system can receive data about the seated occupant in many ways such as position and weight sensors, belt tension sensors, input about the seated occupant (e.g. identity, age, weight) into a vehicle data device prior to operating the vehicle, etc. In addition to allowing or preventing airbag10from deploying, occupant classification system30can also signal airbag10whether a vent38is to be opened or closed during deployment of airbag10.

Venting of airbag10is used to control a stiffness of airbag10during deployment. Controlling stiffness of airbag10during deployment is important due to the wide variation in the size of occupants, the number of seat positions available, and combinations thereof. For example, if the seat's occupant is an average-sized male (e.g., 5 feet 10 inches tall and 160 pounds), a stiffer (i.e., a more fully inflated) airbag10may be desired to more fully cushion the occupant's engagement with airbag10during deployment. In contrast, if an average-sized female, child, or the like is located adjacent airbag10, a softer (i.e., a less than fully inflated) airbag10may be desired to more fully cushion the occupant's engagement with airbag10during deployment. If a stiffer airbag10is engaged by a smaller-sized occupant (such as a child), the occupant may experience injury upon engagement with airbag10. Similarly, if a position of seat is nearer airbag10upon deployment, a softer airbag10is desired, while if a position of seat is farther from airbag10upon deployment, a stiffer airbag10is desired.

To control stiffness of airbag10during deployment, airbag10includes at least one vent38that is selectively controlled. In addition to the selectively controlled vent38, airbag10may be provided with one or more unobstructed or active vents39that facilitate a controlled vent rate of the gas expanding the airbag10during deployment. Selective venting of airbag10through vent38is desirable to selectively adjust stiffness (i.e., an amount of inflation of airbag10) depending on occupant size, seat position, and whether or not a child seat is located adjacent airbag10. For example, if the occupant classification system determines that an occupant falls within a predetermined classification, e.g. within a minimum size and/or within a minimum distance from the bag, the classification system could provide a signal to open the vent during airbag deployment.

To adjust the stiffness of airbag10during deployment, vent38can selectively be opened upon deployment. That is, if a stiffer airbag10is needed during deployment, vent38is to remain closed to allow airbag10to more fully inflate. If a softer airbag10is needed during deployment, vent38is opened upon deployment. That is, as airbag10inflates with vent38opened, an amount of gas used to inflate airbag10is allowed to escape, which softens airbag10.

To selectively control the opening of vent38during deployment, vent38is covered by a selectively actuatable flap40. To actuate flap40, a tether42is attached to flap40. Tether42includes a first end44fixed to flap40, and a second end46detachably fixed to housing12. If vent38is to be opened during deployment, tether42remains fixed to housing12. When tether42remains fixed to housing12and airbag10begins to inflate, first end44of tether42will exit housing12along with airbag10. Once tether42has reached its full length during deployment and remains fixed to housing12, tether42will pull open flap40to expose vent38and allow gas to escape therefrom to soften airbag10. In the exemplary embodiments, the occupant classification system makes a determination about the seated occupant that corresponds to a signal to operate the vent and tether during airbag deployment. The signal to operate the vent and tether based on the determination about the seated occupant may be provided by a controller in communication with the occupant classification system. In another exemplary embodiment, the occupant classification system may be part of a module located in another portion of the vehicle other than a seat. The controller, e.g. an electronic control unit (ECU), may be separated from the module and in communication with another controller, e.g. a controller that directs an operation of a portion of the airbag.

Tether detachment device48may be a guillotine-type detachment device including a blade50that is actuated by ECU37of airbag10during deployment of airbag10. Alternatively, tether detachment device48may be in the form of a pin (not shown) that secures second end46of tether42to housing12. When airbag10is deployed, pin (not shown) may be actuated by ECU37of airbag10to disengage from tether42to allow tether42to detach from housing12. Regardless, it should be understood that a tether detachment device48can be used to detach tether42from housing12if vent38is to remain closed during deployment of airbag10.

FIG. 3illustrates vent38and flap40of airbag10in more detail. Vent38may be circular in shape and includes a diameter in the range of 50 mm to 110 mm. Vent38, however, may have any shape desired. In this regard, vent38may be square, rectangular, triangular, oval, X-shaped, or the like. Preferably, vent38is formed in either side panel20of airbag10, or is formed in rear panel22. Vent38is formed in either side panels20or rear panel22to prevent gases used to inflate airbag10from contacting the seat's occupant in the event of deployment.

As illustrated inFIG. 3, flap40may be formed separately from airbag10. In this regard, flap40may be formed from a piece of fabric that overlaps vent38. To secure flap40to airbag10, flap40may be sewn to airbag10, as indicated by sew lines56. It should be understood, however, that flap40may be attached to airbag10in any manner known to one skilled in the art including, for example, by an adhesive.

Tether42is attached to flap40at a central portion58thereof. Tether42may be attached to central portion58by sewing (illustrated), but may be attached to central portion58in any manner desired so long as tether42remains fixed to central portion58. As illustrated inFIG. 3, central portion58is connected to a remainder of flap40by pre-cuts60. Although four pre-cuts60are illustrated inFIG. 3, any number of pre-cuts60may be used to ensure that central portion58may at least partially detach from flap40to expose vent38if vent38is to be opened during deployment of airbag10.

When airbag10deploys and vent38is to be opened as directed to occupant classification system30, tether42remains fixed to housing12. As airbag10expands, airbag10will expand to an extent where vent38will be located a distance away from housing12that is greater than a length of tether42. Once airbag10has expanded to an extent that is greater than the length of tether42, fixed tether42will pull on central portion58with a force sufficient to at least partially detach central portion58from flap40. That is, tether42will pull on central portion58with a force sufficient to tear portions62of flap40located between pre-cuts60such that central portion58may detach from flap40to expose vent38. When vent38is exposed, the inflation gas may escape from airbag10to allow airbag10to soften.

In contrast, when airbag10deploys and vent38is to remain closed as directed by occupant classification system30, second end46of tether42is detached from housing12by tether detachment device48. As tether42is detached from housing12, even when airbag10expands to an extent that is greater than the length of tether42, vent38will not be exposed because central portion58will remain attached to flap40. As tether42will be detached from housing12, however, airbag10may be provided with a sleeve64. Tether42is passed through sleeve64during fabrication of airbag10. If second end46of tether42is detached from housing12during deployment of airbag10, sleeve64prevents second end46of tether42from flapping throughout the vehicle.