Power transfer assembly for contact-start plasma arc torch

A power transfer assembly for supplying electrical power to an electrode of a contact-start plasma arc torch, the power transfer assembly comprising:

• a conductive static element having a first mating structure defined by first mating structure sidewalls that are parallel to a first mating structure axis, wherein said static element is configured to engage a power supply element of the torch when the assembly is installed into a torch;
• a conductive movable element having a second mating structure that is defined by second mating structure sidewalls that are parallel to a second mating structure axis and which is configured to translatably engage said first mating structure, wherein said movable element is provided by an integral portion of the electrode of the torch;
• a compression spring configured to engage said conductive elements, said conductive elements being configured such that positioning said mating structures to be translatably engaged with each other generates an off-axis force in said spring that acts to bias said mating structures together along at least one line of contact to assure an electrically conductive path through said mating structures, said spring having a coil centered on a spring natural axis when at rest and further wherein said spring engages said conductive elements in such a manner as to apply an off-center force to deflect a portion of said coil away from the spring natural axis when said conductive elements are positioned to slidably engage said mating structures with each other;
• and
• a power transfer housing in which said static element is affixed so as to engage a power supply element of the torch when said power transfer housing is installed into the torch, said power transfer housing having a ledge that limits forward motion of said movable element relative to said static element, said ledge being configured to allow the electrode of the torch to engage said movable element.

A power transfer assembly for supplying electrical power to an electrode of a contact-start plasma arc torch, the power transfer assembly comprising:

• a conductive static element having:
• a static element spring-aligning means that defines a static element alignment axis, and
• a first mating structure defined by first mating structure sidewalls that are parallel to the static element alignment axis;
• a conductive movable element having:
• a movable element spring-aligning means that defines a movable element alignment axis, and
• a second mating structure defined by second mating structure sidewalls that are parallel to the movable element alignment axis, said second mating structure being configured to translatably engage said first mating structure in a direction parallel to the alignment axes;
• and
• a compression spring having a coil, said coil having,
• a coil first end region that engages said static element spring-aligning means so as to be centered on the static element alignment axis, and
• a coil second end region that engages said movable element spring-aligning means so as to be centered on the movable element alignment axis;
• wherein said first mating structure sidewalls are positioned relative to the static element alignment axis and said second mating structure sidewalls are positioned relative to the movable element alignment axis such that positioning said mating structures to be translatably engaged causes the static element alignment axis to be offset from and parallel to the movable element alignment axis, and thus said coil first end region of said spring is displaced off axis with respect to said coil second end region.