Electro-hydraulic directional control valve
US4543875A · kind A · utility
31Cited by
5References
5Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Nov 30, 1983 |
| Grant date | Oct 1, 1985 |
| Priority date | — |
| Expiry date | Nov 30, 2003 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/86614
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A first front face of a main control spool of a main control valve is loaded with a constant pressure, whereas the opposite face is loaded with a controlled pressure to control the fluid passages to and from a hydraulic actuator. The control pressure is adjusted by means of a two-edge control of the pilot control spool of a pilot control valve which is actuated by a single proportional solenoid against the force of a spring. The advantages obtained thereby result in a substantial savings in manufacturing expenditure and a substantially improved control operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.