Patent Application
20090102166
The present invention relates generally to the field of airbags and inflatable safety devices. More specifically, the invention relates to airbags with one or more tearable sleeves so as to maintain the airbags in a folded or rolled up condition during shipping, installation, or handling.
It is known in the art to provide side curtain airbags in vehicles of the safety and protection of the driver and passengers located in the vehicle. The curtain airbags typically include an inflatable portion that runs along the longitudinal direction of the vehicle (as opposed to the traverse direction) and a gas generator in fluid communication with the inflatable portion. The curtain airbag is folded or rolled up into a compact structure and stored in a storage space in the interior roof of the vehicle along the longitudinal direction. At the time of a crash, impact sensors, deceleration sensors or the like trigger the gas generator so as to fill up the inflatable portion of the curtain airbag, which deploys the airbag downward along the side of the vehicle so as to prevent the vehicle passengers and driver from impacting the vehicle's side walls and windows.
When an airbag is folded up, typically, strips of adhesive tape are used to keep the airbag in the folded condition, as seen in
The use of adhesive tape strips have some drawbacks. For example, many strips need to be applied along the longitudinal direction of the airbag so as to keep the entire airbag in the folded condition. Also, peeling of the adhesive tape may occur if the tape loses its adhesiveness. Finally, the tape strips do not maintain the straightness of the folded airbag if the airbag needs to be twisted during installation into the vehicle.
According to one embodiment of the present invention, an airbag module for a vehicle may comprise an airbag for protecting a vehicle occupant and at least one tearable sleeve. The airbag is configured to be in a folded or rolled up state and to deploy along an interior side portion of the vehicle. The at least one tearable sleeve coaxially surrounds a portion of the airbag in the folded or rolled up state in which the at least one tearable sleeve is a shrink wrap film.
According to another embodiment of the present invention, an airbag module for a vehicle may comprise an airbag and at least one tearable sleeve. The airbag comprises an inflatable portion and a connecting portion for connecting a gas generator in which the airbag is configured to be in a folded or rolled up condition. The at least one tearable sleeve is located circumferentially around a portion of the inflatable portion of the air bag when in the folded or rolled up condition. The at least one tearable sleeve is configured to shrink around the inflatable portion of the air bag to provide a form fit after being subjected to an application of heat.
It is to be understood that both the foregoing general description and the following detailed descriptions are exemplary and explanatory only, and are not restrictive of the invention as claimed.
These and other features, aspects and advantages of the present invention will become apparent from the following description, appended claims, and the accompanying exemplary embodiments shown in the drawings, which are briefly described below.
Description of various embodiments of the present invention will be described in reference to the figures.
Attached to the airbag 202 is a gas generator 204, which is used to inflate the airbag during an event of an emergency. The airbag 202 itself may include one or more inflatable portions 206 divided by seams 208, a passage way 210 that allows fluid communication between the gas generator 204 and the inflatable portions 206, and a series of mounting tabs 212. The mounting tabs 212 includes one or more apertures 214, which are used to mount the airbag to the frame or other supporting structure in the vehicle through the use of alignment pins being fed through the apertures 214.
The airbag 202 may be typically folded or rolled up before it is to be stored, transported, and/or mounted in the vehicle, as seen in
After the airbag 202 is folded or rolled up, one or more tearable sleeves 300 are slid across the longitudinal direction of the airbag. The tearable sleeve(s) may be made from a shrink wrap film material, which has the ability to shrink from an expanded state with a larger diameter (as seen in
According to one embodiment, the tearable sleeve may be a shrink wrap film, preferably made from polyethylene terephthalate (PETG) polyester but it should be recognized that other suitable materials may be used such as, for example, polyvinyl chloride (PVC), polyolefin, neoprene rubber, Vinton rubber, FEP or PTFE.
Preferable properties of the tearable sleeve may include: a shrink factor in the range of about 50 to about 90%, preferably about 70%; and a thickness in the range of about 0.5 to about 5 mils, preferably about 2 mils. The tearable sleeves may shrink from the expanded state to the contracted state when the application of heat raises the temperature of the tearable sleeve.
According to one embodiment, the tearable sleeves are continuous loops of material, for example shrink wrap tubing. Alternatively, the tearable sleeve may be sheets of film that are wrapped around the airbag, and upon the application of heat, are shrunk and the ends are melted together so as to provide form fitting loops.
In either the tubing or wrapped sheet arrangements, the length of the tubes or sheets may be varied depending on need. As a result, any number of tearable sleeves may be used around portions of the airbag, such as one, two, three, four, five, six, seven (as seen in FIGS. 3-4) or more. The sleeve may extend circumferentially around inflatable portions of the airbag and/or portions that include non-inflatable portions.
Once the one or more tearable sleeves are placed in a suitable position along the folded or rolled up airbag, the assembly may be placed through a heat tunnel or ran past one or more heat guns mounted on an assembly line so as to shrink the tearable film from the expanded state (as seen in
The airbag module 600 assembly is then placed into a storage compartment or location 610 located along the interior roof 608 of the vehicle as seen in
By providing a tearable sleeve in this fashion, multiple pieces of adhesive tape for holding the rolled up or folded airbag may be replaced by a fewer components, which decrease the assembly time and material costs. For example, up to 22 or 23 pieces of adhesive tape may need to be used to provide a state in which the airbag is prevent from being unrolled or unfolded. In contrast, only 4 pieces of tearable sleeves may accomplish the same purpose. Also, the number of personnel may be decreased by using mounted heat guns on an assembly line or a heat tunnel instead of the manual operation of applying the pieces of adhesive tape around the airbag.
In some applications, the airbag may need to be twisted during the installation of the airbag module 600 into the storage compartment or location 610, for example 90 degrees. In such a case, the tearable sleeves provide the added benefit of keeping the airbag module straighter than if strips of adhesive tape are used, as seen in
In the embodiment of
Additionally, the tearable sleeve 802 may be affixed with a label so as to provide suitable identifying information, such as a bar code, the name of the manufacturer, the model or type of airbag module, and/or the like.
Given the disclosure of the present invention, one versed in the art would appreciate that there may be other embodiments and modifications within the scope and spirit of the invention. Accordingly, all modifications attainable by one versed in the art from the present disclosure within the scope and spirit of the present invention are to be included as further embodiments of the present invention. The scope of the present invention is to be defined as set forth in the following claims.
