Electronically controlled cryopump
US4918930A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 13, 1988 |
| Grant date | Apr 24, 1990 |
| Priority date | — |
| Expiry date | Sep 13, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S417/901
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A cryogenic vacuum pump includes, in an integral assembly, temperature sensors and heaters associated with the first and second stages of the cryopumping array, a roughing valve and a purge valve. An electronic module removably coupled in the assembly responds to all sensors and controls all operations of the cryopump including regeneration thereof. System parameters are stored in a nonvolatile memory in the module. Included in the regeneration procedures are an auto-zero of the pressure gauge, heating of the array throughout rough pumping, and a change in pressure rate test to determine stall in rough pumping. The electronic module also restarts the system after power failure, limits use of a pressure gauge to safe conditions, provides warnings before allowing opening of the valves while the cryopump is operating and stores sensor calibration information. Control through a control pad on the pump may be limited by a password requirement. Password override is also provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.