| 摘要 |
An air bag of the type utilized in a vehicle occupant restraint system is constructed of a plurality of panels of uncoated fabric. Respective of the panels have been processed to achieve a selected air permeability with greater accuracy on a lot-to-lot basis than had generally been achieved with uncoated fabrics of the prior art. In one presently preferred methodology, the panels are first calendered under selected temperature and pressure conditions such that a low reference permeability is achieved. Next, respective of the panels may be needled such that the permeability is raised from the low reference permeability to a selected permeability level. Alternatively, a plurality of fluid jets, preferably water jets, may be utilized to impact panels of the uncoated fabric under selected operating conditions. Pores created by the fluid jets may be heat set to achieve a selected permeability. |
