System and method for inflation gas filtration through a tortuous flow pathway

摘要

An airbag assembly may include an airbag and an inflator that provides inflation gas to inflate the airbag. A filter module may be positioned such that inflation gas exiting the inflator must first pass through the filter module. The filter module may be formed of a sheet of metal that is wrapped into a generally tubular shape. The filter module may have a first layer and a second layer that generally encircles the first layer. The first layer may have a pattern of holes and dimples that are separate from and/or displaced from each other. The dimples may protrude toward the second layer to maintain spacing to enable relatively unrestricted gas flow from the holes of the first layer through unaligned holes of the second layer. The resulting tortuous gas flow path may help to slow, cool, and/or purify the gas before it exits the inflator.

主权项

1. An inflator for an airbag assembly for protecting a vehicle occupant from injury, the inflator comprising:
an exterior wall comprising a first aperture; a gas source contained within a chamber defined within the exterior wall, wherein, in response to receipt by the inflator of a first activation signal, the gas source provides a gas; and a filter module made from a sheet wrapped in a spiral configuration comprising a first layer and a second layer, wherein:
the first layer is a first segment of the sheet and comprises a first plurality of holes, wherein the first layer is positioned such that the gas passes through the first plurality of holes to reach the second layer;the second layer is a second segment of the sheet and comprises a second plurality of holes, each hole of the second plurality of holes is not aligned radially with each hole of the first plurality of holes, wherein the second layer is positioned such that the gas passes through the second plurality of holes to reach the first aperture; andone of the first layer and the second layer comprises a first plurality of dimples, wherein each dimple of the first plurality of dimples protrudes toward the other of the first layer and the second layer to maintain an open spacing between the first layer and the second layer for the gas to flow along a tortuous pathway through the open spacing from the first plurality of holes to the second plurality of holes, wherein each dimple of the plurality of dimples is separate from each hole of the corresponding plurality of holes.