Thermal Dynamics Corporation

Jesse A Roberts

Kevin D Horner-Richardson

David A Small

Gene V Hewes

Geoffrey H Putnam

Milind G Kelkar

A plasma arc torch and method for improving the life of the consumable parts of the plasma arc torch, including the electrode, the tip and the shield cap. The method includes turbulating gas as it flows over the exposed surfaces of the electrode, tip and shield cap to increase turbulence in the hydrodynamic boundary layer of the gas flow, thereby enhancing convective heat transfer. The result of enhanced cooling is improved consumable parts life. For example, to increase the turbulence of the gas flow over the outer surface of the electrode, the plasma arc torch electrode has a roughened, or textured outer surface formed with dimples, axially extending grooves or spiraling grooves formed in the outer surface of the electrode. The inner and outer surfaces of the tip and the inner surface of the shield cap are similarly textured.

Plasma arc torch and method for improved life of plasma arc torch consumable parts

A plasma arc torch and method for cutting a workpiece in which the torch has a primary gas flow path for receiving a primary working gas and directing it through the torch to a central exit opening of the torch for exhaustion from the torch onto the workpiece in the form of an ionized plasma. A secondary gas flow path in the torch receives a secondary gas separate from the primary working gas and directs it through the torch. The primary gas flow path is in fluid communication with the secondary gas flow path substantially upstream of the central exit opening of the torch to bleed primary working gas in the primary gas flow path into the secondary gas flow path for admixture therewith to form a secondary gas mixture to be exhausted from the torch.

Plasma arc torch and method for cutting a workpiece

A plasma arc torch has a cathode and electrode having connecting ends configured for a coaxial telescoping connection with one another on a central longitudinal axis of the torch. The connecting ends have interengageable detents thereon, with at least one of the detents being movable in a generally radial direction relative to the central longitudinal axis of the torch between an undeflected state and a deflected state. The at least one detent is movable from the undeflected state to the deflected state when the cathode and electrode are telescoped one into the other, and is movable from the deflected state back toward the undeflected state when the cathode and electrode are further telescoped tc, a point where the detents on the cathode and electrode are generally axially aligned. In this position, the at least one detent is engageable with the other detent to interconnect the cathode and electrode and inhibit axial movement of the electrode away from the cathode.

Growing community of inventors

Milton, VT, United States of America

Jesse A Roberts