Pilot operated four way valve
US4169490A · kind A · utility
Inventor
Key dates
| Filing date | Jun 3, 1977 |
| Grant date | Oct 2, 1979 |
| Priority date | — |
| Expiry date | Jun 3, 1997 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/87225
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A pilot valve for reversing the flow of fluid in a pair of pipes. The valve is less complex than prior art devices serving the same purpose, comprising in essence four aligned rolling diaphragm devices which are automatically controlled by the presence, or absence, respectively of pilot pressure. If pilot pressure is present, a flow of fluid under pressure is established in one of two pipes and the other is vented. On the other hand, if pilot pressure is removed, the pipe in which a flow of fluid under pressure had been established is vented and a flow of fluid under pressure is established in the pipe which has been previously vented. The output of the pipe in which a flow of pressure is established may be used to operate and to reverse the operation of a cylinder and piston machine, such as, for instance, a pneumatic or fluid motor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.