US Patent 6946616 Plasma arc torch cooling system

A cooling system for a plasma arc torch is provided that comprises a coaxial fluid flow that improves cooling of components within the plasma arc torch and that provides a more compact torch design. The coaxial fluid flow, namely, the cooling fluid flow, is distributed circumferentially about the central longitudinal axis of the torch and is flowing in the same direction at any radial location from the central longitudinal axis. The cooling fluid flows distally towards the consumable components, then proximally towards the torch head, then distally again, and then proximally again for recirculation. Additionally, both the plasma gas flow and the secondary gas flow are also flowing coaxially in addition to the cooling fluid flow.