Patent ID: 7415995

Claim:
A canister filling system, comprising: first and second fill stations configured to receive and independently fill canisters with pressurized gas; first and second storage stations storing gas at corresponding first and second charge pressures, respectively, the first and second storage stations being prioritized in a cascaded manner; a supply-chain independently joining each of the first and second fill stations to both of the first and second storage stations; and first and second valve sub-assemblies provided in the supply-chain, the first and second valve sub-assemblies monitoring, independent of one another, canister pressures at the corresponding first and second fill stations, the canister pressure representing a pressure within a corresponding canister, the first and second valve sub assemblies automatically opening and closing to permit and prevent discharge of gas from the first and second storage stations, independent of one another, to automatically switch between the first and second storage stations based on the priority and the canister pressures.