Proportional pressure control valve with control port pressure stabilization
US7343934B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 15, 2005 |
| Grant date | Mar 18, 2008 |
| Priority date | — |
| Expiry date | Oct 10, 2026 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/8671
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A proportional pressure control valve which includes an electric first stage pilot having a single outlet port configured to provide a variable pressurized hydraulic fluid to the outlet port and at a pressure that is proportional to an electric input signal and which is variable between first and second values and further includes a second stage hydraulic valve which has a spool reciprocally moveable in a bore between first and second positions indicative of a full ON and a full OFF condition. A fluid isolation chamber is oriented in the bore and in a region between a control port and a tank port in the fluid pathway therebetween. The interior wall of the bore and the first and second diameter regions on the spool are configured to always provide a controlled volume fluid flow rate between the control port and the fluid isolation chamber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.