Abstract: This invention concerns gas filled thyratrons and is concerned with preventing the formation of arc spots on the grid when the thyratron is operated in a grounded grid mode. The thyratron provided has a grid consisting of three apertured baffle electrodes which are electrically united and occur in sequence in the cathode to anode path of the thyratron. The baffle electrodes on the cathode side of the final baffle electrode forms at least one re-entrant hollow cathode and conductive gauze covered apertures in the baffle electrodes on the cathode side of the final baffle electrode are staggered relative to apertures in the final baffle electrode.

Abstract: A thyratron is provided with a baffled structure between its cathode and first control electrode. The baffled structure consists of a series (e.g. three) annular baffle plates, each having a central aperture aligned with the axis of the cathode, mounted on the end of a cylindrical heat shield surrounding the cathode. The final annular baffle plate, adjacent the first control electrode includes a solid disc within its central aperture.

Abstract: A circuit interrupting device for providing protection against surge currents is constructed to operate very rapidly. A surge current generates a magnetic field in coils which deflects an electron beam which normally travels from a cathode to an anode to complete an electric circuit.