Inflator for an inflatable vehicle occupant protection device

An inflator (10) includes a housing (12) containing a body (60) of ignitable gas generating material, a body (48) of pyrotechnic material, and an electrically conductive structure (40,44,46) for igniting the body (48) of pyrotechnic material. A closure cap (28) closes the housing (12), and has a passage (190) extending along an axis (18). A tubular structure (220) directs combustion products from the body (48) of pyrotechnic material toward the body (60) of gas generating material, and has an installed position extending axially in the passage (190). The tubular structure (220) and the closure cap (28) have interlocking structures (198,232) for interlocking the tubular structure (220) with the closure cap (28) upon movement of the tubular structure (220) to its installed position in the passage (190).