Patent ID: 6860510

Claim:
A multistage inflating hybrid inflator comprising an inflator housing having an axial direction and a radial direction, a first gas generating chamber and a second gas generating chamber each provided with a gas generating agent which is accommodated in the inflator housing, a first ignition chamber and a second ignition chamber provided with first and second igniters, respectively, each of which is independently connected to the two one of said first and second gas generating chambers, a diffuser portion connected to the inflator housing and provided with a gas discharging port, a pressurized medium charged inside the inflator housing, and a principal rupturable plate closing between the inflator housing and the diffuser portion, wherein the first gas generating chamber and the second gas generating chamber are arranged radially within said inflator housing in parallel with each other and spaced apart from each other, the first gas generating chamber and the second gas generating chamber are provided with one or two or more first communication holes which communicate the first gas generating chamber with the inflator housing and one or two or more second communication holes which communicate the second gas generating chamber with the inflator housing, respectively, and the first communication holes and the second communication holes are provided such that the first communication holes do not directly oppose the second communication holes so that heat energy generated in the first gas generating chamber is prevented from flowing into the second gas generating chamber to ignite the gas generating agent therein.