Low tone axial fan structure
US6599085B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 18, 2001 |
| Grant date | Jul 29, 2003 |
| Priority date | — |
| Expiry date | Sep 18, 2021 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF04D29/326
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A low tone axial flow fan structure includes a hub 12; an inner fan 14 including a number of inner blades 16 attached to the hub and extending radially outwardly to a first circumferentially extending blade support structure 18; and an outer fan 20 including a number of outer blades 22 attached to the first circumferentially extending blade support structure 18 and extending radially outwardly to a second circumferentially extending blade support structure 20. The number of outer blades defines an outer fan blade passing order. The number of inner blades ensures creation of blade passing orders or multiple of said blade passing orders within one blade passing order of the outer fan blade passing order so as to provide masking of the outer fan blade passing order.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.