| 摘要 |
1,049,057. Welding by fusion. D. SCIAKY. Sept. 21, 1964 [June 11, 1964], No. 38366/64. Heading B3R. [Also in Divisions F1 and H1] In electron beam welding apparatus in which the electron beam is brought out from a vacuum chamber 14 through an open orifice 36 on to the workpiece 46, 47 located in a region of higher pressure, e.g. the atmosphere, the orifice 36 is the exit end of a nozzle 33 and an inert gas which is introduced at 45 to flow under pressure in a surrounding nozzle 38 produces a Venturi action to assist in maintaining the vacuum in the chamber 14. The gas may flow at supersonic speed. An ion trap electrode is provided at 48; the nozzles are surrounded by cooling ducts and pipes 60, 61; and magnet coils 50, 58 serve to confine the beam within the nozzle and to focus the beam at the workpiece. In a modification part of the pressurized gas is diverted to flow parallel to the electron beam and is discharged across the opening through which the beam emerges on to the workpiece and an intermediate chamber, connected to a vacuum pump, is provided between the anode 28 and a partition wall from which the nozzle 33 depends. |
