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:
Oct. 01, 1991
Filed:
Jul. 11, 1990
Applicant:
Inventors:
Assignee:
IBM Corporation, Armonk, NY (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F01D / ;
U.S. Cl.
CPC ...
4151821 ; 415119 ; 415206 ;
Abstract
A centrifugal fan includes a brushless d.c. motor, an impeller mounted on the motor and a scroll on which the motor is mounted. The scroll defines the air inlet and outlet and has an outer wall curved around the impeller to define a divergent air flow path. By truncating the scroll at the outlet substantially to eliminate any flat portions on the outer wall susceptible to mechanical vibrations at frequencies excited by the d.c. motor, a noise reduction is achieved. Further noise reduction may be achieved by resiliently mounting the motor on the scroll.