Airbag deployment trajectory control mechanism and method

A system and method of inflating an airbag and trajectory control tube are disclosed. The system and method include detecting application of a force at at least one of a plurality of sensors, initiating an inflation system to cause inflation of the airbag and the trajectory control tube responsive to the detecting, inflating the trajectory control tube based on the initiating, inflating the airbag, and breaching the airbag and the trajectory control tube compartment. The system and method include guiding the airbag deployment trajectory via the trajectory control tube guides the airbag deployment trajectory. The system and method include the guiding occurs as the airbag begins to inflate, as the airbag inflates, after the airbag has inflated or before the airbag inflates.

FIELD OF INVENTION

The present invention is related to airbag deployment and particularly to the control of the trajectory of airbag deployment.

BACKGROUND

Airbag deployment trajectory is an important consideration in airbag restraint system design. Good deployment trajectory may enhance protection for occupants and avoid inflation induced injuries to out-of-position (OOP) occupants. In the past, the restraint system suppliers have used airbag shape and the assembly of fabric pieces, tethers inside the airbag, airbag folding pattern, and inflator nozzle orientation to attempt to control airbag deployment trajectory. The old methods have required trial-and-error techniques and can provide less than optimal outcomes. Therefore, a need exists to improve the control the trajectory of airbags during deployment in order to protect occupants and reduce injuries to OOPs.

SUMMARY

A system and method of inflating an airbag and trajectory control tube are disclosed. The system and method include detecting application of a force at at least one of a plurality of sensors, initiating an inflation system to cause inflation of the airbag and the trajectory control tube responsive to the detecting, inflating the trajectory control tube based on the initiating, inflating the airbag, and breaching the airbag and the trajectory control tube compartment. The system and method include guiding the airbag deployment trajectory via the trajectory control tube. The system and method include the guiding that occurs as the airbag begins to inflate, as the airbag inflates, after the airbag has inflated or before the airbag inflates.

A passive restraint system is also disclosed. The passive restraint system includes an airbag that is capable of deploying upon impact to restrain the body of at least one occupant and at least one trajectory control tube adhered to the airbag, the at least one trajectory control tube capable of guiding the airbag deployment trajectory. The passive restraint system includes the guiding that occurs as the airbag begins to deploy, as the airbag deploys, after the airbag has deployed or before the airbag deploys.

An automobile including a passive restraint system is also disclosed. The automobile includes an airbag that is capable of deploying upon impact to restrain the body of at least one occupant and at least one trajectory control tube adhered to the airbag, the at least one trajectory control tube capable of guiding the airbag deployment trajectory. The automobile includes the guiding that occurs as the airbag begins to deploy, as the airbag deploys, after the airbag has deployed or before the airbag deploys.

DETAILED DESCRIPTION

FIG. 1illustrates an airbag and associated inflation device depicted in an uninflated state100. Airbag and associated inflation device100includes an airbag110, a trajectory control tube120, an inflation system130, a sensor or plurality of sensors140. As shown inFIG. 1, airbag and associated inflation system100is depicted within a steering wheel assembly including a steering wheel150and a steering wheel compartment160. While shown within the steering wheel, airbag and associated inflation device100may be located in a myriad of different locations as would understood to those possessing an ordinary skill in the pertinent arts, and as will be set forth herein below.

In an implementation airbag110is made of thin, nylon fabric and folded into steering wheel compartment160or other compartment in the vehicle. As is known to those possessing an ordinary skill in the art, airbag110may be part of a passive vehicle restraint system within a vehicle, the airbag110designed to rapidly inflate on impact to restrain the body of an occupant or occupants, often above torso level, to prevent direct contact with the vehicle structure.

Airbag110may have associated therewith a trajectory control tube120. Trajectory control tube120may also be made of thin, nylon fabric. Trajectory control tube120may be included within airbag110(as shown) or may be adjacent to airbag110. Airbag110and trajectory control tube120may be inflated by inflation system130. As shown a single inflation system130may be used for the inflation of both airbag110and trajectory control tube120, although multiple inflation systems130may be used for inflation of airbag110and/or trajectory control tube120. While a single trajectory control tube120and/or airbag110is discussed in the examples below, the present invention encompasses the use of multiple trajectory control tubes120and/or multiple airbags110.

Inflation system130may include an inflator mechanism, such as a chemical reaction to produce a large pulse of gas. This gas inflates airbag110and trajectory control tube120causing airbag110and trajectory control tube120to burst out of steering wheel compartment160or other compartment as airbag110and trajectory control tube120expand. The breaching of steering wheel compartment160may be caused by the inflation trajectory control tube120without any inflation of airbag110, by the inflation of airbag110without any inflation of the trajectory control tube120, or may be caused by a combination of the inflation of trajectory control tube120and airbag110with any combination between the trajectory control tube120and airbag110. Airbag110and trajectory control tube120are deflated as appropriate during the energy absorption phase of interaction with the vehicle occupant.

Inflation system130may be controlled or initiated by a single or series of signals from a sensor or plurality of sensors140. Sensors140may detect an impact or deceleration of the vehicle and provide a signal to inflation system130to initiate inflation of airbag110and trajectory control tube130. Sensors140send an electric signal to inflation system130to fill airbag110and trajectory control tube120. Sensors140may be located throughout the vehicle, generally at the periphery of the vehicle, such as in the doors, and in the center of the vehicle in the front and back.

FIG. 2illustrates an airbag and associated inflation device depicted in an inflated state200. WhileFIG. 2is representation of an airbag and inflation device,FIG. 2provides illustration of the parts of the present invention and is not intended to provide an actual depiction of the shape or configuration of an actual inflated airbag.

Airbag and associated inflation device200is a depiction of the inflated state of the airbag and associated inflation device100ofFIG. 1. Airbag and associated inflation device200includes an airbag210, a trajectory control tube220, an inflation system230, a sensor or plurality of sensors240. As shown inFIG. 2, airbag and associated inflation system200is depicted within a steering wheel assembly including a steering wheel250and a steering wheel compartment260.

Upon application of a force245, or otherwise initiating sensor240a signal is provided to inflation system230causing initiation of inflation235. This inflation results in airbag210and trajectory control tube220inflating and breaching compartment260.

FIG. 3illustrates a method of inflating an airbag and trajectory control tube300. Method300includes detecting application of a force at at least one of a plurality of sensors at step310. At step320, method300includes initiating the inflation system to cause inflation of airbag and trajectory control tube. At step330, method300includes inflating the trajectory control tube. Inflating the trajectory control tube guides the airbag deployment trajectory as the airbag begins, or continues to inflate at step330. Method300includes inflating the airbag at step330and breaching the airbag and trajectory control tube compartment at step350.

As set forth, inflating the trajectory control tube guides the airbag deployment trajectory. This guiding may occur before the airbag inflates, as the airbag begins to inflate, as the airbag inflates, and/or after the airbag has inflated.

By way of example, in an implementation illustrated inFIG. 4a diffuser plate400that may be used to control the flow of gas into the airbag and trajectory control tube. The diffuser plate400may include a main body430that mounts the diffuser plate400to the airbag (not shown) and the trajectory control tube (not shown). A series of holes410a, b, c, dmay be provided allowing the gas contained on one side of the diffuser plate400to expand and inflate the airbag. A second series of holes420(shown as only a single larger hole in the depiction) may be used to direct the expanding gas into the trajectory control tube. The ratio of the area of the airbag holes410a, b, c, dand the trajectory control tube holes420may be used to control the respective rates of inflation of the airbag and trajectory control tube to allow the trajectory control tube to inflate more quickly than the airbag to provide the guiding forces to position the airbag as desired during and for inflation. Other mechanisms for controlling the inflation of the trajectory control tube and airbag may be used while the implementation ofFIG. 4illustrates only one way of performing the inflation by example only. These other mechanisms include having separate inflators for each, for example.

By way of non-limiting example only, other mechanisms may employ a tear seam in the trajectory control tube. The trajectory control tube seam may be configured such that during initial inflation all, or the majority, of the gas is directed into the trajectory control tube causing the trajectory control tube to become completely filled. Once the trajectory control tube becomes filled and the pressure in the tube reaches a certain level, the trajectory control tube seam tears open and allows gas from the trajectory control tube to then proceed into the main airbag. Any continual gas filling the trajectory control tube at this point may proceed into the main airbag.

While a tear seam is described above, other forms of pressure relief may be used. This pressure relief may include a device or devices that react to the pressure, or a switchable device that is triggered at the appropriate time, allowing the trajectory control tube to open as if the seam is there. This opening may include a valve or something similar that opens and allows gas to flow into the main airbag.

These examples may be employed in the present system to cause the trajectory control tube to inflate ahead of the main airbag, for example. The air flow may also be controlled allowing the airbag to begin inflating while the trajectory control tube is inflated. The timing may be controlled such that the trajectory control tube fills ahead of the main airbag, in conjunction with the main airbag, or even after the main airbag for example.

FIG. 5illustrates an exemplary trajectory control tube120. Trajectory control tube120may be condensed into a non-filled tube depicted as non-filled tube550. One end of trajectory control tube120may be coupled to the main body430of diffuser plate400and may be filled upon activation of the gas via an opening, hole or series of holes420.

Upon application of gas, non-filled tube550becomes filled with gas via hole420and expands from the non-filled state to take the shape defined by the materials and geometry of the trajectory control tube120. This may include a first side510of trajectory control tube120and a second side520of trajectory control tube120illustrated in the two-dimensional depiction ofFIG. 5. Once inflated with gas, trajectory control tube120defines the location of the distal end530of trajectory control tube120. The distal end530defines a point or plane in space distal to the diffuser plate400base on the specific geometry of the design of trajectory control tube120). The placement of distal end530defines the guiding that trajectory control tube120performs in locating the airbag (not shown). That is, the airbag may be adhered to trajectory control tube120via end530to locate a portion of the airbag at the same point as end530. Since distal end530may be positioned by controlling the geometric parameters of trajectory control tube120, the portion of the airbag adhered to distal end530is also similarly located, thereby defining the position of the airbag. The airbag and trajectory control tube may be adhered by being sewn together, glued together, or alternatively the airbag may have a chute in which the trajectory control tube resides.

Alternatively, or additionally, there also may be no physical attachment between the trajectory control tube120and the airbag110. The present invention may be designed to be achieved through friction/sliding interaction between, or among, the trajectory control tube and airbag. The use of friction may be beneficial when the main airbag is folded within the chamber and the trajectory control tube pushes against different areas of the main airbag as it unfolds.

FIG. 6illustrates a dashboard of a vehicle to provide areas where the present trajectory control tube may be implemented. By way of non-limiting example only, the present trajectory control tube and airbag may be deployed in the steering wheel610, above center on the dashboard620, in the center console620, and below center on the dashboard640. The airbag may also be located within the ceiling of the vehicle (not shown), the door of the vehicle (not shown), the seat where the airbag is deployed to protect the occupant seated in the seat (not shown) and/or the seat where the airbag is deployed to protect the occupant seated behind the seat (not shown). The trajectory control tube described above may be utilized to control the direction and placement of the airbag once deployed.

Having thus described the presently preferred embodiments in detail, it is to be appreciated and will be apparent to those skilled in the art that many physical changes, only a few of which are exemplified in the detailed description of the invention, could be made without altering the inventive concepts and principles embodied therein. It is also to be appreciated that numerous embodiments incorporating only part of the preferred embodiment are possible which do not alter, with respect to those parts, the inventive concepts and principles embodied therein. The present embodiments and optional configurations are therefore to be considered in all respects as exemplary and/or illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all alternate embodiments and changes to this embodiment which come within the meaning and range of equivalency of said claims are therefore to be embraced therein.