Apparatus for hydraulically adjusting the blades of an impeller of an axial-flow fan
US7971519B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 6, 2008 |
| Grant date | Jul 5, 2011 |
| Priority date | — |
| Expiry date | Jun 3, 2029 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04D27/008
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An apparatus for hydraulically adjusting the blades of an impeller of an axial-flow fan, comprising an adjustment cylinder that on both sides of a piston displaceably disposed in the cylinder has a first chamber and a second chamber respectively provided with a connection to control oil lines connected to four-way valves. Not only a feed line leading to one of the control oil lines, but also a return line connected to the other control oil line, is each divided into two parallel branch lines. Two redundant four-way valves are provided, each being disposed in one of the parallel branch lines. Disposed in each branch line of each control oil line, between the respective connection and the respective four-way valve, is a seat valve that closes by spring force.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.