Circular knitting machine for large articles

摘要

The apparatus has an X-ray source (3) having an electron source (31) and a stationary anode (4) which describes a full or partial anode ring with a circuit for accelerating electrons emitted from the electron source, using a high positive constant voltage, towards the anode ring. The electrons form an electron beam (32) which collides with the anode ring at a focal spot (41) which, in turn, emits X-ray radiation in the form of a fan beam (42). With a full or partial X-ray detector ring (5) the detector ring and the anode ring are coaxially arranged and define a scan slice. The detector ring is such as to permit the spatial resolution around the ring of the X-rays detected. A number of electron sources are arranged on an electron source ring (33) in proximity to the anode ring. A circuit is provided to control the sources individually in order to emit electron beams in set time sequence. The focal spots produced by the electron beams on the anode ring are each electromagnetically swept over a portion of the anode ring.