System and method for recovering from a power failure in a cryopump
US6510697B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 2001 |
| Grant date | Jan 28, 2003 |
| Priority date | — |
| Expiry date | Jun 7, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S417/901
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
In a power failure recovery, the operating state before a power failure and present conditions of a cryopump are determined to initiate a regeneration or startup process. Where the refrigerator was operating before power failure, it is turned on during recovery to condense gases in the cryopump. A startup process is initiated where the cryopump was in a startup process before the power failure and present conditions of the cryopump indicate that the cryopump is sufficiently empty or clean. If the operating state and present conditions indicate that a corrosive or hazardous liquid remains in the cryopump, a regeneration process is initiated. If the cryopump was in a shutdown process before the power failure, the cryopanel of the cryopump is refrigerated to a temperature at which gases sublimate from the cryopanel. The temperature of the cryopanel is then maintained until the gases are removed. A refrigerator having a displacer with variable speed and heaters may be used to control the temperature of the cryopanel. When the cryopump is sufficiently empty, the cryopump is turned off.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.