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Expired Canadian patentCanada

Cooling fan with reduced noise for variable speed machinery

CA 2018816 C · Owner: Ford Motor Company · Inventors: Nelson, David Arthur

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

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Abstract From the Canadian patent

A centrifugal fan for ventilated rotating machinery is provided having tapered fan blades to reduce sound pressure levels generated by fan operation over a wide speed range. The tapering of the fan blades keeps the cross-sectional area of each flow channel substantially constant as the air flows radially through the fan, resulting in a less turbulent flow. Each fan blade may include a height profile having a tapered segment in which blade height decreases in proportion to increasing radial distance from the central axis of the fan.

Read the whole patent

Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Filed June 12, 1990 and granted November 10, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 12, 2010.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 12, 2012.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledJune 12, 1990
GrantedNovember 10, 1998
Term endedJune 12, 2010
Patent numberCA 2018816 C
Classification (IPC)H02K9/06 +2 more

Timeline

Timeline From CIPO dates

1991199319951997199920012003200520072009Application filedJune 12, 1990Patent grantedNov 10, 1998Term endedJune 12, 2010

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.