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:
Jan. 13, 1998
Filed:
Sep. 04, 1996
Shigeru Otsuka, Yonago, JP;
Abstract
An air moving device for improving P-Q characteristics and noise by suppressing the production of vortices. An annular wall spaced from blade tips, is formed of a plurality of annular plates and spacers with a slit defined between adjacent annular plates. The width of each slit is set to satisfy the formula W.ltoreq.(.nu..multidot.R.sub.ec /v) where .nu. is the kinematic viscosity of air, v is the peripheral speed of the blade tips, W is the width of the slits and R.sub.ec is the critical Reynold's number. Thus, as a fan is rotated, air is drawn in a laminar flow through the slits to the inner periphery of the annular wall. Thereby, it is possible to suppress the separation of air flow on the suction side of blade surfaces and the production of vortices, thus improving the air moving state.