Abstract:
An electric discharge device has a cold cathode of solid, easily vaporizable material, and a triggering arrangement comprising a dielectric member, disposed near the cathode and anode, and having on one side a sputtered film of easily vaporizable material and on the other side a trigger electrode. The device operates at high vacuum, and a discharge can be triggered by applying a voltage pulse to the trigger electrode, causing vaporization of material from the film. For example, the device may be a switching device, a travelling-wave device, or an ion propulsion device.
Abstract:
Triggerable electric arc discharge device includes coaxial cathode and anode electrodes defining therebetween a hollow cylindrical primary arcing gap. A trigger assembly having an elongated longitudinal configuration is inserted into a longitudinal bore formed in and adjacent to the surface of the cathode electrode so as to be partially exposed into the interelectrode gap. Trigger assembly includes a ceramic hollow cylinder surrounding a metallic trigger electrode. Trigger gap is defined by extension of the trigger electrode past the inboard end of the trigger ceramic insulator and a trigger gap exists between the extended portion of the trigger electrode over the inboard end of the ceramic insulator and to the body of the cathode electrode. A voltage is connected between anode and cathode electrodes and a relatively low voltage pulse is supplied to the trigger electrode, causing breakdown of the trigger gap. Trigger arc formed thereby causes propulsion of ionized specie into the main gap and breakdown thereof.