The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 13, 2014
Filed:
Jan. 05, 2009
Suguru Nakagawa, Sakai, JP;
Jirou Yamamoto, Osaka, JP;
Suguru Nakagawa, Sakai, JP;
Jirou Yamamoto, Osaka, JP;
Daikin Industries, Ltd., Osaka, JP;
Abstract
A propeller fan includes a huband a plurality of blades, which are radially arranged on the outer circumference of the hub. A plurality of bent surface-shaped recessestoare formed on the positive pressure surface at a trailing edgeof each blade. The recessestoextend in the rotation direction of the fan and are arranged in a radial direction. Protrusionsare each formed between adjacent pair of the recessesto. The bent surfaces of the recessestoand the protrusionsreduces air flow caused by centrifugal force. This allows the air flow on the positive pressure surface of the bladeto easily flow along the recessesto. As a result, air flow does not concentrate on the outer periphery of the blade, which reduces the differences in the velocity and volume of air flow between the outer tipof the bladeand the hub. Accordingly, the bladefunctions as a whole. Therefore, the air blowing performance (efficiency and air blowing noise) of the propeller fan is improved.