Combination check and flow control valve for hydraulic systems
US4204459A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 19, 1978 |
| Grant date | May 27, 1980 |
| Priority date | — |
| Expiry date | Apr 19, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/87241
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A hydraulic system including a hydraulic pump, a hydraulic motor having at least one port and a hydraulic reservoir. A main spool valve is interposed between the motor and the pump and reservoir and has a spool shiftable between positions connecting the pump to the port, connecting the reservoir to the port, and blocking fluid flow to or from the port. A single combination check and flow control valve is interposed between the main spool valve and the port. A fluid responsive surface opens the combination valve to permit relatively free flow of fluid therethrough when the spool is in the first mentioned position thereof. A pressure responsive surface and a control valve provides for partial opening of the combination valve to meter fluid flow therethrough when the spool is in the second position thereof. A spring is operative to close the combination valve to prevent fluid flow therethrough when the spool is in the last mentioned position thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.