Open center unloading valve
US4655250A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 3, 1986 |
| Grant date | Apr 7, 1987 |
| Priority date | — |
| Expiry date | Feb 3, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/87185
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
An unloading valve utilized in an open center hydraulic system in conjunction with a conventional open center control valve having an open center passage and a dead end power passage; the unloading valve is supplied by a system pressure from a pump and divides the pump flow into two paths in a set proportion regardless of the amount of flow or pressure levels in either flow path, one flow path is directed to reservoir with the other flow path directed to the open center passage in the directional control valve while the dead end power passage of the control valve is separately provided with system pump pressure in a parallel path whereby only a portion of the pump discharge passes across the open center passage when the directional control valve is neutrally positioned.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.