Patent ID: 7974384

Claim:
An x-ray tube comprising: a vacuum enclosure; a shaft having a first end and a second end, wherein the shaft includes a passageway therein and an opening to the passageway at the second end, and wherein the passageway is tapered along an axis from the first end to the second end; a diffuser positioned within the passageway and forming a gap between an outer wall of the diffuser and an inner wall of the passageway, the diffuser configured to pass a coolant therethrough; a flange attached to the first end of the shaft, the flange having an outer perimeter; and a ferrofluid seal assembly having an inner bore, the inner bore having an outer perimeter smaller than the outer perimeter of the flange; wherein the shaft is inserted through the bore of the ferrofluid seal assembly such that the ferrofluid seal assembly is positioned between the first end of the shaft and the second end of the shaft and such that the first end extends into the vacuum enclosure; and wherein the ferrofluid seal is configured to fluidically seal the vacuum enclosure from an environment into which the second end of the shaft extends.