Air propellers in so far as the profile of their blades is concerned
US4773825A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 17, 1986 |
| Grant date | Sep 27, 1988 |
| Priority date | — |
| Expiry date | Nov 17, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S416/02
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
The invention relates to improvements to air propellers in so far as the profile of their blades is concerned. The law of evolution of the curvatures of the extrados 2 is the following: the curvature, maximum at the leading edge A, increases first of all rapidly to reach a value of about 4 at the point B at about 4% of the length of the chord, and then decreases regularly to reach a substantially zero value at the trailing edge F. The law of evolution of the curvatures of intrados 3 is the following: the curvature, maximum at the leading edge A, decreases first of all rapidly to reach a value of about 8 at a point D at about 3.5% of the length of the chord, then decreases less rapidly to reach a zero value at a point E situated between 10% and 60% of the length of the chord, decreases further to a slightly negative value and then remains practically constant as far as the trailing edge F.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.