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:
Jun. 12, 2007
Filed:
Oct. 20, 2004
Applicants:
Jonathan E Mccallum, Edmonton, CA;
Andrew L Norell, St. Albert, CA;
Inventors:
Jonathan E McCallum, Edmonton, CA;
Andrew L Norell, St. Albert, CA;
Assignee:
Flexxaire Manufacturing Inc., Edmonton, CA;
Primary Examiner:
Int. Cl.
CPC ...
F04D 29/36 (2006.01);
U.S. Cl.
CPC ...
Abstract
Pitch control of a variable pitch fan is obtained using pulsed pressure. Pitch is varied incrementally either towards or away from full pitch by pulsed application of fluid to a piston used to drive the blades of the fan into or away from full pitch. Reverse pitch is used to clear debris from the fan. Valves control flow of fluid to the piston. The valve operation is controlled by a controller.