Air bag module inflator retainer

In an air bag module including a generally circular inflator and a base plate having a circular plate opening, a mechanism for attaching the inflator to the base plate comprising:

• a plurality of stud members mounted to the base plate in a predetermined circular pattern about the plate opening and extending downwardly from the base plate, each of the stud members including a radial slot facing the plate opening, the slots cooperatively defining a predetermined circular diameter;
• the inflator including a peripheral outwardly extending inflator flange underlying and engaging the base plate upon insertion of the inflator through the plate opening, the inflator flange including a plurality of flange openings aligned for receiving the stud members therethrough such that the slots in the stud members open subjacent the inflator flange when the inflator flange engages the base plate;
• and
• an inflator retainer being a discontinuous resilient ring having a relaxed position in which the retainer has a diameter greater than the diameter defined by the slots, the retainer having a partially contracted position in which the retainer has a diameter less than the diameter defined by the slots, the retainer being radially contractible for insertion between the stud members and, upon radial alignment with the slots, the retainer being releasable to the partially contracted position for snap-fitted engagement within each of the slots such that the retainer is captured and held therein whereby the inflator flange is trapped between the retainer and the base plate such that the inflator is anchored to the base plate and held in position relative to the base plate when discharging gas.

A method of assembling an inflator to a base plate which includes the base plate having a circular opening, a plurality of stud members mounted to the base plate in a predetermined circular pattern, each of the stud members including a radial slot facing the plate opening and cooperatively defining a predetermined diameter, a generally cylindrical inflator including an outwardly extending inflator flange having a plurality of flange openings for receiving the stud members therethrough, and an inflator retainer being a discontinuous, resilient, circular ring which is radially contractible, the retainer having a relaxed position in which the retainer has a diameter greater than the diameter defined by the slots, the retainer having a partially contracted position in which the retainer has a diameter less than the diameter defined by the slots, comprising the steps of:

• a. aligning the stud members with the inflator flange openings and inserting the inflator through the plate opening such that the inflator flange engages the base plate and the slots in the stud members open subjacent the inflator flange;
• b. radially contracting the retainer for insertion between the stud members and radially aligning the retainer with the slots;
• and
• c. releasing the retainer for outward radial expansion to the partially contracted position such that the retainer snap-fittedly engages each of the slots and is captured and held in the slots such that the inflator flange is trapped between the retainer and the base plate whereby the inflator is anchored to the base plate.