Rotary vane pump with ballast port
US4826407A · kind A · utility
3Cited by
5References
13Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 21, 1987 |
| Grant date | May 2, 1989 |
| Priority date | — |
| Expiry date | Oct 21, 2007 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04C2220/50
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
Rotary vane pump with ballast ports which introduce air into the swept cells before they reach the pump outlet port. To prevent overheating at very high vacuums, the ballast ports are arranged to provide a ratio of ballast air flow to pump displacement, at a standard working vacuum of 20 inches Hg gauge, of at least 35%. This permits operating at 25 inches Hg gauge without the need for a cooling fan.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.