Method and apparatus for quickly heating a vacuum tube cathode
US4675573A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 23, 1985 |
| Grant date | Jun 23, 1987 |
| Priority date | — |
| Expiry date | Aug 23, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J23/04
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Disclosed are a method and apparatus for rapidly heating a thermionic vacuum tube cathode, thereby enabling the vacuum tube to be placed in useful operation shortly after the tube is switched on. Rapid heating of the cathode is achieved by passing current through the cathode, thereby directly heating it. Simultaneously, the cathode is also heated by an indirect radiant heater and by electron bombardment by electrons emitted from the heater. When the cathode reaches its operating temperature, the direct heating current and the electron bombardment are stopped and the cathode is maintained at its operating temperature by the indirect heater alone. Cathode warm-up times of less than 1 second may be attained using this invention.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.