Two-way hydraulic valve with one way time delay
US5205321A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 21, 1991 |
| Grant date | Apr 27, 1993 |
| Priority date | — |
| Expiry date | Nov 21, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/7792
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A two-way, inline, hydraulic valve through which fluid can flow in reverse and in forward directions has a reverse flow passage including a check valve preventing forward direction fluid flow therethrough. Forward direction fluid flow is controlled by a movable, spring-biased, normally closed, spool valve having one end exposed to forward direction fluid pressure and an opposite end forming a piston acting in a cylindrical cavity containing a volume of fluid. Movement of the spool valve to open position in response to forward direction fluid pressure sufficient to overcome the spring bias causes the volume of fluid to be forced from the cavity through a restricted passage, thereby providing a time delay in the opening of the two-way valve for forward direction fluid flow. In an alternative embodiment, a sleeve valve mounted on the spool valve provides a by-pass permitting forward direction fluid flow under abnormally low forward direction fluid pressure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.