Systems, devices, and methods for starting plasma
Some embodiments herein are directed to devices and methods for automatically starting a plasma utilizing a wand. In some embodiments, the wand may be used to start a plasma in a plasma torch such as, for example, a microwave plasma torch or an induction plasma torch, as discussed below. The wand may comprise an elongate, hollow wand member comprising a closed distal end, a proximal end, and one or more apertures extending from a hollow interior of the wand member to an exterior surface of the wand member; and an elongate wire member positioned within the hollow interior of the wand member and extending along at least a portion of a length of the wand member, wherein the wire member is configured to be placed in operable communication through the aperture with a power source, such that the power source can be activated to in turn start the plasma within the plasma torch. The plasma torches discussed herein may be used in various applications including, for example, high volume synthesis of advanced materials such as nano-materials, micro-powders, coatings, alloy compositions for additive manufacturing.
1. A device for starting a plasma of a plasma torch, the device comprising:
an elongate, hollow wand member located within a plasma chamber of the plasma torch, the wand member comprising a closed distal end, a proximal end, and one or more apertures proximate to the closed distal end extending from a hollow interior of the wand member to an exterior surface on a lateral side of the wand member; and
an elongate wire member comprising one or more wires positioned within the hollow interior of the wand member and extending along at least a portion of a length of the wand member, wherein the wire member is configured to be placed in operable communication through the one or more apertures with a power source, such that the power source is activated to in turn start the plasma within the plasma torch,
wherein the wire member is configured to remain within the hollow interior of the wand member when the plasma is started, and
wherein the wand member encloses the wire member within the plasma torch except at the one or more apertures.
2. The device of claim 1 , wherein the power source comprises a microwave generator, and wherein a length of the wire member comprises ¼ of a wavelength or longer of a microwave generated by the microwave generator.
3. The device of claim 1 , wherein the wand member comprises between 1 and 100 apertures.
4. The device of claim 1 , wherein the wire member comprises one wire.
5. The device of claim 1 , wherein the wire member comprises more than one wire.
6. The device of claim 1 , wherein the wand member comprises quartz or another microwave-transparent material.
7. The device of claim 1 , wherein the wire member comprises a metal or metal alloy.
8. The device of claim 1 , wherein the wand member comprises an open proximal end.
9. The device of claim 1 , wherein the wire member extends at least from a position proximate the closed distal end to a position outside of the proximal end.
10. The device of claim 1 , wherein the wand member comprises a plurality of apertures proximate the closed distal end of the hollow wand member.
11. The device of claim 1 , wherein the wire member is fused to the hollow interior of the wand member.
12. The device of claim 1 , wherein the wand member is in operable communication with a motor and a gas flow of the plasma torch.
13. The device of claim 12 , wherein the motor is configured to impart motion on the wand member to place the wand member within the plasma torch, such that the wire member is configured to be placed in operable communication through the aperture with the power source and the gas flow.
14. The device of claim 12 , wherein the motor is configured to move the device into the gas flow of the plasma torch.
15. The device of claim 14 , wherein moving the device into the gas flow places the wire member in operable communication through the aperture with the power source.
16. The device of claim 12 , wherein the motor is configured to move the device out of the gas flow of the plasma torch.
17. The device of claim 12 , wherein the motor is in operable communication with a control unit, the control unit programmed to provide one or more control signals to the motor.
18. The device of claim 17 , wherein the control unit is configured to transmit an instruction to the power source to start the plasma of the plasma torch.
19. The device of claim 1 , wherein the wand member is in operable communication with a limit switch comprising an actuator for determining a location of the wand member.