Direction control valve
US5725022A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 10, 1996 |
| Grant date | Mar 10, 1998 |
| Priority date | — |
| Expiry date | Sep 10, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/87885
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A direction control valve is constructed in such a manner that a spool bore having an inlet port, an actuator port and a tank port is formed in a valve block, a spool slidable between positions for establishing and blocking communication of the input port, the actuator port and the tank port, is disposed within the spool bore, the input port and the tank port open to a first mateable surface and a second mateable surface of the valve block, and a plurality of the valve blocks are stacked and connected with mating the first mateable surface and the second mateable surface for establishing communication between the input ports and between the tank ports of the valve blocks. An annular groove is formed in the second mateable surface of the valve block at a position outside of the ports, a drain confluence passage communicating with the annular groove is formed with opening in the first mateable surface and the second mateable surface, an oil seal for sealing between the spool bore and the spool is provided and the back surface side of the oil seal is communicated with the annular groove.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.