Full flow pressure trap unloader valve
US5755251A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 28, 1995 |
| Grant date | May 26, 1998 |
| Priority date | — |
| Expiry date | Nov 28, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/2647
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An unloader valve for a high pressure pumping system is disclosed. The unloader valve diverts fluid back to the pump inlet when the discharge line is blocked, and directs flow to the pump outlet when the line is unblocked. The unloader valve includes a valve body with a central cavity, a bypass check valve which also functions as a pressure relief valve, a shuttle positioned in the central cavity and a discharge check valve. A spring in the bypass check valve holds the bypass check valve closed while the system is in the spray mode. The discharge check valve closes when the line is blocked, and the line pressure is trapped between the discharge check valve and the spray gun. When the gun is reactivated, the pressure trapped behind the discharge check valve moves the shuttle forward, which opens the bypass valve.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.