Patent ID: 8102969
Filing Date: 2012-01-24
Classification: H01J

Abstract:
1. An x-ray device comprising: an evacuated tube housing; a cathode in said tube housing that emits an electron beam; a rotating anode unit mounted in said tube housing to rotate around a rotational axis; said rotating anode unit comprising an anode plate having a target region on which said electron beam is incident to emit x-rays therefrom with an associated generation of heat, and a shaft connected to said anode plate at a first side of said anode plate; a magnetic bearing that provides contact-free magnetic support of said shaft to allow rotation of said shaft and said anode plate in said housing; a receptacle in said tube housing having a receptacle wall, said receptacle containing a thermally conductive fluid; and an axial extension extending from said anode plate at a second side thereof, opposite said first side, said axial extension projecting into said receptacle and forming a gap between said axial extension and said receptacle wall in a range between 100 μm and 200 μm, said thermally conductive fluid filling said gap and forming a non-bearing heat dissipater that conducts said heat away from said anode via said axial extension.