GB1359121A - Target for x-ray tubes - Google Patents

Abstract

1359121 X-ray tubes MACHLETT LABORATORIES Inc 14 July 1972 [2 Aug 1971] 33128/72 Heading HID An anode for an X-ray tube comprises atarget member having an area available for X-ray emission greater than any projected area thereof and held in contact with a backing member. In the rotary anode shown in Fig. 3 a wire 60 is closely wrapped round a target ring 36 which is clamped between two backing rings 38 and 48; the turns of the wire run radially to avoid intercepting any emitted X-rays, and as illustrated the backing ring 38 may be provided with a ridge 72 adapted to enter a corresponding groove in ring 36 to tighten the wire. The wire may be of tungsten, rhenium-tungsten, or molybdenum and may be 0.008 inch diameter for a large focal spot of 1.5-2 mm width (as seen at 64 in the direction of X-ray emission) or 0.003-0.005 inch for a small focal spot of 0.3-1 mm. The backing rings 38 and 48 may be of graphite, tungsten, or molybdenum. In a modification (Figs. 7 and 8, not shown), the target ring is provided with radial grooves. In another construction (Fig. 9, not shown) a fixed anode member is covered with a wire winding, the wires running in the direction of inclination of the anode surface to avoid intercepting X-rays.