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Expired Canadian patentCanada

Interlocking cross tee

CA 2015106 C · Owner: Worthington Armstrong Venture · Inventors: Platt, William J.

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 fire-resistant suspended ceiling grid structure having cross tees interlocked to main beams to support, ceiling tiles. The structure has shear able means to permit a cross tee to expand into a main beam during a fire. The interlock includes tongues held in an abutting relationship by open belt loops. The tongues slide to permit the cross tees to expand longitudinally during a fire.

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 April 20, 1990 and granted October 22, 1991. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 20, 2010.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 20, 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.
FiledApril 20, 1990
GrantedOctober 22, 1991
Term endedApril 20, 2010
Patent numberCA 2015106 C
Classification (IPC)E04B9/00 +1 more

Timeline

Timeline From CIPO dates

1991199319951997199920012003200520072009Application filedApril 20, 1990Patent grantedOct 22, 1991Term endedApril 20, 2010

Sources & verification

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