Torch with rotational start

摘要

A plasma arc torch has a threadless electrode-cathode locking assembly, a one-piece tip assembly, and a rotational contact starting mechanism. The cathode and electrode of the locking assembly are configured such that relative rotation of the electrode with respect to the cathode causes the electrode to move in an axial direction relative to the cathode for locking the electrode in fixed axial and rotational position with respect to the cathode. The inner wall of the one-piece tip assembly is configured to receive the forward end of the electrode in a non-contact position. Rotation of the electrode with respect to the tip causes an arcing formation on the electrode to contact an arcing chamber within the cavity. Rotation of the electrode away from the tip generates a pilot arc in the arcing chamber.