Ring tube x-ray source
US5268955A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1992 |
| Grant date | Dec 7, 1993 |
| Priority date | — |
| Expiry date | Apr 8, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2235/162
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A toroidal x-ray tube housing (A) has an evacuated interior. An annular anode (B) is connected with the housing closely adjacent the window such that a cooling fluid passage (12) is defined in intimate thermal communication with the anode. A cathode assembly (32) is mounted within the evacuated housing or an annular ring (30) that rotates an electron beam (22) around the large diameter annular anode. In the embodiment of FIGS. 1 and 2, the annular ring is magnetically levitated (40) and rotated by a motor (50). A collimator (62) and filter (64) are rotated with the cathode assembly closely adjacent an electron emitter or cathode cup (32) such that the generated x-rays are collimated and filtered within the x-ray tube. Preferably, a plurality of cathode cups (120) are provided, whose operation is selected by a series of magnetically controlled switches (76). The cathode cup is insulated (106) from the annular ring and isolated by a transformer (104, 112) from the filament current control switches. In the embodiment of FIGS. 4-6, the cathode assembly (C) includes a multiplicity of stationarily mounted electron cups (120) which are selectively actuated to rotate the electrode beam by …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.