Lift valve for rotary screw compressors
US4737082A · kind A · utility
5Cited by
5References
6Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jan 28, 1987 |
| Grant date | Apr 12, 1988 |
| Priority date | — |
| Expiry date | Jan 28, 2007 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04C28/16
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
When regulating the capacity of a rotary screw compressor in a refrigeration and heating pump system and when varying the built-in volume therein, lift valves are used which operate instantaneously and are either open or closed. In order to ensure sufficient pressure on the lift valves to effect closing, the wall of the lift valves is shaped with two different diameters and a sharply defined step therebetween. Upon closing, the sharply defined step is influenced by a pressure which is lower than the pressure influencing the end surfaces of the lift valve.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.