# US 2009/0260233 A1 · Method of producing a high voltage stable cathode for an x-ray tube > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2009/0260233 A1 - Document ID: US20090260233A1 - Status: Published application - Kind: A1 - Application number: 12/495,886 - Filed: 2009-07-01 - Published: 2009-10-22 - Earliest claimed: 2005-06-30 - Assignees: General Electric Company - Inventors: Sergio Lemaitre - Web page: https://patentgrep.com/patent/US20090260233A1 ## CPC - H01J 35/066: {Details of electron optical components, e.g. cathode cups} - H01J 1/13: Solid thermionic cathodes - H01J 9/04: of thermionic cathodes - Y10T 29/49204: Contact or terminal manufacturing - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A method of producing a cathode for use in an x-ray tube assembly is provided including machining an emission aperture into a cup emission surface portion of a cup structure. The cup structure is comprised of a cup base portion opposite the cup emissions surface portion. Electro-discharge machining is used to form an electro-discharge machining slot into the cup structure to provide access to the interior of the cup structure. Electro-discharge machining is used to form a transverse coil chamber within the interior by way of the electro-discharge machining slot such that the transverse coil chamber is formed between the cup base portion and the cup emissions surface portion while retaining an essentially contiguous emissions surface perimeter surrounding the emission aperture. ## Claims ### Claim 1 A method of producing a cathode for use in an x-ray tube assembly comprising: machining an emission aperture into a cup emission surface portion of a cup structure, said cup structure comprising a cup base portion opposite said cup emissions surface portion; electro-discharge machining an electro-discharge machining slot into said cup structure to provide electro-discharge machining access to the interior of said cup structure; electro-discharge machining a transverse coil chamber into said interior through said electro-discharge machining slot such that said transverse coil chamber is formed between said cup base portion and said cup emissions surface portion, said cup emissions surface portion therein retaining an essentially contiguous emissions surface perimeter surrounding said emission aperture. ### Claim 2 (depends on 1) The method of producing a cathode for use in an x-ray tube assembly as described in claim 1, wherein said electro-discharge machining comprises wire electro-discharge machining. ### Claim 3 (depends on 1) The method of producing a cathode for use in an x-ray tube assembly as described in claim 1, wherein said contiguous emissions surface parameter comprises: a first ear portion; a second ear portion; a first side bridge formed between said first ear portion and said second ear portion; and a second side bridge formed between said first ear portion and said second ear portion. ### Claim 4 (depends on 1) The method of producing a cathode for use in an x-ray tube assembly as described in claim 1 further comprising machining a plurality of upper aperture edges surrounding said emissions aperture to generate a radiused perimeter. ### Claim 5 (depends on 1) The method of producing a cathode for use in an x-ray tube assembly as described in claim 1, further comprising electro-discharge machining said transverse coil chamber to generate a large transverse coil slot; a small transverse coil slot; and a separation pillar positioned between said large transverse coil slot and said small transverse coil slot. ### Claim 6 (depends on 5) The method of producing a cathode for use in an x-ray tube assembly as described in claim 5, further comprising electro-discharge machining said electro-discharge machining slot into said cup emission surface portion such that said electro-discharge machining slot is aligned over said separation pillar. ### Claim 7 (depends on 6) The method of producing a cathode for use in an x-ray tube assembly as described in claim 6, further comprising machining a plurality of radiused entrance edges onto said electro-discharge machining slot where said electro-discharge machining slot intersects said cup emission surface portion. ### Claim 8 (depends on 1) The method of producing a cathode for use in an x-ray tube assembly as described in claim 1, wherein said electro-discharge machining slot enters said cup structure through a rear surface of said cup base portion. ### Claim 9 (depends on 1) The method of producing a cathode for use in an x-ray tube assembly as described in claim 1, wherein said electro-discharge machining slot enters said cup structure through a side surface of said cup base portion. ### Claim 10 (depends on 9) The method of producing a cathode for use in an x-ray tube assembly as described in claim 9, wherein said electro-discharge machining slot enters said transverse coil chamber at a rearward region. ### Claim 11 (depends on 9) The method of producing a cathode for use in an x-ray tube assembly as described in claim 9, wherein said electro-discharge machining slot enters said transverse coil chamber at a forward region. ### Claim 12 A method of producing a cathode for use in an x-ray tube assembly comprising: machining an emission aperture into a cup emission surface portion of a single piece cup structure, said cup structure comprising a cup base portion opposite said cup emissions surface portion; wire electro-discharge machining a electro-discharge machining slot into said cup structure to provide wire electro-discharge machining access to the interior of said cup structure; and wire electro-discharge machining a transverse coil chamber into said interior through said electro-discharge machining slot such that said transverse coil chamber is formed between said cup base portion and said cup emissions surface portion, said cup emissions surface portion therein retaining an essentially contiguous emissions surface perimeter surrounding said emission aperture. ### Claim 13 (depends on 12) The method of producing a cathode for use in an x-ray tube assembly as described in claim 12, further comprising machining a plurality of radiused entranced edges around said essentially contiguous emissions surface perimeter.