Axial-flow fan
AssigneeUsui Kokusai Sangyo Kaisha Limited
InventorTetsunobu Suzuki
Life of this patent
Estimating the term…
Abstract
An axial-flow fan having a high fan efficiency and high performance is provided by improving a fluid flow on the rear edge side of a blade tip without deteriorating the fluid flow on the front side of the blade tip, and reducing loss of horsepower without causing a large influence on loadings. The blade has a warped portion on the side surface of the blade tip on the rear edge side thereof, being formed by bending the blade tip toward upstream at angles between 5 to 30 degrees with a smooth filet R along a line C connecting a position along the blade tip at the chord length A to 1/5 A from the rear edge of the blade tip toward the front edge of the blade tip and a position along the radial length B of the blade at 1/2B to 1/10B from the rear edge of the blade tip.
Claims1
An axial-flow fan comprising a plurality of fan blades disposed in the circumferential direction at desired intervals, characterized in that the blade has a warped portion on the side surface of the blade tip on the rear edge side thereof, the warped portion is formed by bending the blade tip toward upstream at angles between 5 to 30 degrees with a smooth filet R along a line C connecting a widthwise position along the blade tip at a length between A and 1/5A, where A represents the chord length A, from the rear edge toward the front edge thereof and a radial position of the rear edge of the blade at a radial length between 1/2B and 1/10B from the rear edge of the blade tip, where B represents the radial length of the blade.
Dependencies are inferred from the claim text.