Patent Yard Sign in
Expired Canadian patentCanada

Covered split scroll for centrifugal blower

CA 2013480 C · Owner: Chou, S. T. Rudy · Inventors: Hogan, Mark Roland; Chou, S. T. Rudy

CIPO record

Overview

Drawings and full text

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

Open the CIPO record

Abstract From the Canadian patent

A split scroll diffuses and directs air upwards from the circumference of a forwardly-curved centrifugal fan to a discharge plane to one side of the fan. The scroll has a first monotonically increasing curved wall that extends from a cutoff point near the circumference of the rotor in, the direction of rotation, to the discharge plane. A second monotonically increasing curved wall extends in the opposite direction from the cutoff point up to the discharge plane. The first and second curved walls are mirror images of one another taken at the plane corresponding to the air flow tangent that passes through the cutoff point. A curved cover above the fan at the exit plane blocks line of sight …

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 March 30, 1990 and granted January 18, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 30, 2010.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 30, 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.
FiledMarch 30, 1990
GrantedJanuary 18, 1994
Term endedMarch 30, 2010
Patent numberCA 2013480 C
Classification (IPC)F04D17/00 +2 more

Timeline

Timeline From CIPO dates

1991199319951997199920012003200520072009Application filedMarch 30, 1990Patent grantedJan 18, 1994Term endedMarch 30, 2010

Sources & verification

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