Mixing cold plasma beam jets with atmopshere
The present disclosure is directed to an electrosurgical apparatus for generating plasma in electrosurgical applications. The electrosurgical apparatus includes an end effector disposed on a distal portion of a tube of the electrosurgical apparatus. The end effector mixes ambient air with an inert gas to increase the production of radical species. In one aspect of the present disclosure, the end effector includes a cylindrical augmenter disposed over a distal end of the tube with one or more tilted vanes disposed between the cylindrical augmenter and the tube. In another aspect of the present disclosure, the end effector includes one or more tilted vanes disposed on an inner surface of a wall of the distal end of the tube. In another aspect of the present disclosure, the end effector includes one or more advection apertures on the wall of the distal end of the tube.
1. An electrosurgical apparatus comprising:
a housing having a passage extending therethrough;
a gas flow tube having a proximal end and a distal end, the proximal end of the gas flow tube being at least partially disposed in the passage of the housing;
an electrode disposed within the gas flow tube and configured to be energized to form plasma at the distal end of the gas flow tube when an inert gas flows through the gas flow tube; and
a cylindrical augmenter including a distal end and proximal end, the cylindrical augmenter concentrically disposed around the distal end of the gas flow tube, wherein when the inert gas flows through the gas flow tube, the cylindrical augmenter is configured to create a Venturi effect to draw ambient air into an annular space between the proximal end of the cylindrical augmenter and the gas flow tube to mix the ambient air with the insert gas to increase radical species production in the plasma.
2. The electrosurgical apparatus of claim 1 , wherein the cylindrical augmenter includes at least one first tilted vane coupled to an inner surface of the cylindrical augmenter and to an exterior surface of the gas flow tube, the at least one first tilted vane configured to impart a tangential velocity component to the ambient air drawn into the annular space between the proximal end of the cylindrical augmenter and the gas flow tube.
3. The electrosurgical apparatus of claim 2 , wherein the gas flow tube includes at least one second tilted vane disposed on an inner surface of the gas flow tube.
4. The electrosurgical apparatus of claim 3 , wherein the at least one first tilted vane is tilted in a different direction than the at least one second tilted vane.
5. The electrosurgical apparatus of claim 1 , further comprising at least one tilted vane disposed on an inner surface of the gas flow tube, the at least one tilted vane configured to impart a tangential velocity component to the inert gas.
6. The electrosurgical apparatus of claim 1 , further comprising at least one advection aperture in a distal portion of a wall of the gas flow tube.
7. The electrosurgical apparatus of claim 6 , further comprising at least one deflection hood coupled to the gas flow tube, the at least one deflection hood configured to at least partially cover the at least one advection aperture.
8. The electrosurgical apparatus of claim 7 , further comprising at least one tilted vane disposed on an inner surface of the gas flow tube.
9. The electrosurgical apparatus of claim 1 , wherein the cylindrical augmenter includes at least two tilted vanes diametrically opposed on an inner surface of the cylindrical augmenter to impart a tangential velocity component to the ambient air drawn into the annular space between the proximal end of the cylindrical augmenter and the gas flow tube.
10. An electrosurgical apparatus comprising:
a housing having a passage extending therethrough, the housing having a proximal end and a distal end;
an electrically conducting tube having a proximal end and a distal end, the electrically conducting tube at least partially disposed in the passage of the housing;
an insulating outer tube having a proximal end and a distal end, the insulating outer tube disposed around the electrically conducting tube with the proximal end of the insulating outer tube coupled to the distal end of the housing, the electrically conducting tube being movable along a longitudinal axis of the housing and insulating outer tube;
an electrode coupled to the distal end of the electrically conducting tube, wherein, in a first position of the electrically conducting tube, the electrode extends beyond the distal end of the insulating outer tube and, in a second position of the electrically conducting tube, the electrode is retracted within the insulating outer tube and is energized via the electrically conducting tube to form plasma when an inert gas flows through the electrically conducting tube; and
a cylindrical augmenter including a distal end and proximal end, the cylindrical augmenter concentrically disposed around the distal end of the insulating outer tube, wherein when the inert gas flows through the electrically conducting tube, the cylindrical augmenter is configured to create a Venturi effect to draw ambient air into the annular space between the proximal end of the cylindrical augmenter and the insulating outer tube to mix the ambient air with the inert gas to increase radical species production in the plasma.
11. The electrosurgical apparatus of claim 10 , wherein the cylindrical augmenter includes at least one first tilted vane coupled to an inner surface of the cylindrical augmenter and to an exterior surface of the insulating outer tube, the at least one first tilted vane configured to impart a tangential velocity component to the ambient air drawn into the annular space between the proximal end of the cylindrical augmenter and the insulating outer tube.
12. The electrosurgical apparatus of claim 11 , wherein the insulating outer tube includes at least one second tilted vane disposed on an inner surface of the insulating outer tube.
13. The electrosurgical apparatus of claim 12 , wherein the at least one first tilted vane is tilted in a different direction than the at least one second tilted vane.
14. The electrosurgical apparatus of claim 10 , further comprising at least one tilted vane disposed on an inner surface of the insulating outer tube, the at least one tilted vane configured to impart a tangential velocity component to the inert gas.
15. The electrosurgical apparatus of claim 10 , further comprising at least one advection aperture in a distal portion of a wall of the insulating outer tube.
16. The electrosurgical apparatus of claim 15 , further comprising at least one deflection hood coupled to the insulating outer tube, the at least one deflection hood configured to at least partially cover the at least one advection aperture.
17. The electrosurgical apparatus of claim 16 , further comprising at least one tilted vane disposed on an inner surface of the insulating outer tube.
18. The electrosurgical apparatus of claim 10 , wherein the cylindrical augmenter includes at least two tilted vanes diametrically opposed on an inner surface of the cylindrical augmenter to impart a tangential velocity component to the ambient air drawn into the annular space between the proximal end of the cylindrical augmenter and insulating outer tube.