Electron beam apparatus and high-voltage discharge prevention method
US6949752B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Nov 18, 2002 |
| Grant date | Sep 27, 2005 |
| Priority date | — |
| Expiry date | Nov 18, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/0206
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Disclosed is an electron beam apparatus and method which can retain the state that minimizes the amount of water content contained at a gap between a high-voltage cable and a high-voltage introduction insulator to thereby prevent creation of high-voltage discharge and current leakage. The apparatus comprises a means for applying a high voltage to an acceleration electrode while eliminating electron release from an electron source and for detecting a change in an emission current corresponding to a change in an acceleration voltage at this time. In addition, the apparatus comprises a means for issuing a cautionary notice or warning when the change of this emission current exceeds a prespecified value. Further, the apparatus comprises a means for letting a dry gas flow in a gap portion between the electron gun's high-voltage cable and the high-voltage introduction insulator to thereby dehumidify said gap portion. With such an arrangement, it is possible to prevent high-voltage discharge due to an increase in water content of the gap portion and also instability of an electron beam due to a leakage current.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.