Method and apparatus for positioning a charged particle beam

摘要

A method and apparatus for seam welding by means of a charged particle beam is disclosed, wherein any misalignment of the beam with respect to the gap between opposed surfaces of two workpiece parts to be joined is compensated for by a double deflection of the beam. The position of the beam in respect to the gap is determined at two locations spaced in the direction of propagation of the beam, and the deflection in two spaced deflection zones is controlled in response to the result of such determination so that the deflected beam-which may oscillate transversely to the longitudinal direction of the gap-is aligned to the gap and a sound weld seam is produced.