Abstract:
The electron beam B is projected on work W, usually in the atmosphere outside of the chamber where the beam is generated, through a plurality of aperture members 11, 13, 15, 17. The holes in the aperture members are as small as practicable to suppress the feedback of air into the chamber. The beam B is focussed in regions 85 and 87 (FIG. 3) with reference to the aperture members so as to preclude damage to the members by impingement of the beam on the walls of the holes through which the beam passes. The beam current is varied in dependence on the demands of the work but the focus of the beam is maintained by bias resistor 115 (FIG. 1), without damage to the aperture member, by instantaneous change in the bias impressed on the beam by a control electrode G.
Abstract:
Electron-beam welding apparatus, particularly for welding work in the atmosphere outside of the vacuum chamber 33 (FIG. 1 in which the electron-beam is generated, which includes facilities for producing X-rays for monitoring of the welds. Such X-rays are produced by projecting the electron beam which serves for welding on an X-ray target 61 at intervals (FIGS. 2, 2A) during the welding operation or during an interval following the welding (FIG. 1); the X-rays may also be produced by deflecting the welding electron beam at intervals on the target (FIG. 5) or by an auxiliary beam generated within the same container as the welding beam (FIG. 4). Where there is an auxiliary beam, the Xray monitoring of the weld may take place continuously as the welding progresses. A method of welding with an electron beam in which the welds are monitored by radiographic analysis while the welding is progressing. An X-ray generator 171 (FIG. 6) in which an electron beam E, which is projected outside of the vacuum chamber in which the electron-beam is generated, produces X-rays by impinging on a consumable target 191 preferably of relatively small dimensions.
Abstract:
To provide a gettering action in relatively high-power vacuumtype circuit interrupters, an active gettering material, such as titanium, tantalum, columbium, zirconium, tungsten or molybdenum is incorporated in the electrode structures or interior elements of a vacuum-type circuit interrupter, so as to be subjected to the heat of the arc, which is established during circuit interruption. By the raising of the temperature of the gettering materials, or agents, their gas-absorption characteristics are activated. The gettering materials are incorporated as filaments, or rods, either disposed randomly, or in parallel alignment in a matrix of good conducting material, such as copper or silver, in the contact portions, so as to be subjected to the heat of arcing.