Centrifugal fan with variable blade pitch
US4662819A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 10, 1986 |
| Grant date | May 5, 1987 |
| Priority date | — |
| Expiry date | Apr 10, 2006 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04D29/282
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A centrifugal fan includes a fan wheel having airfoil blades mounted for pivotal movement about their center of gravity. A yoke mechanism exterior of the fan wheel, when moved axially of the fan wheel drive shaft axis, causes actuator rods to move through the sidewall of the fan wheel. The axial movement of the actuator rods is translated first into rotary movement of a quill hub relative to the fan wheel and finally to radial movement of blade pivoting levers interior of the fan wheel. The movement of the blade pivoting levers causes the pitch of the individual fan blades to be changed in accordance with the degree of movement of the yoke mechanism. The yoke mechanism, actuator rods, quill hub and blade pivoting levers operate independently of the fan wheel so that blade pitch can be varied over an operating range irrespective of whether the fan wheel is stopped or is rotating. The yoke mechanism is moved and fan modulation is accomplished in response to the demand for conditioned air by the variable air volume system in which the fan is employed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.